There’s a moment, right after the potatoes come out of the oven, when the kitchen smells like a French bistro married an Italian trattoria: butter sizzling with rosemary, garlic just this side of golden, and the unmistakable crackle of potato skin that shatters like thin ice under your fork. That moment is why I make these crispy smashed potatoes at least twice a week from October through March, and why my friends start texting me around 4 p.m. on Sundays: “Are you making those potatoes?”

I first stumbled on the technique ten years ago when I was recipe-testing for a holiday menu and ran out of countertop space for a mandoline. I boiled baby potatoes because they cook fast, then accidentally pressed one flat with a coffee mug while reaching for the salt. I flung it onto a hot sheet pan with some duck fat left from the previous night’s roast, and the rest is family-lore history. Since then I’ve refined the method—using a two-step salt brine, adding a cornstarch dredge for extra lacy edges, and finishing with a shower of herbs that practically glow against the amber potatoes. The result is a side dish that eats like a main: crunchy, creamy, herbaceous, and deeply comforting. Serve it beside a reverse-sear ribeye, tuck it under a soft-boiled egg for brunch, or eat them straight off the tray with a glass of chilled white Burgundy while the rest of dinner figures itself out.

Why This Recipe Works

Double-cook method: boiling first, then roasting guarantees a fluffy interior and shatter-crisp exterior.
Alkaline water: baking soda in the boil breaks down pectin for extra fluffy edges that blister.
Cornstarch toss: a light dusting absorbs surface moisture and amps up crunch factor.
Herb-infused oil: warming garlic and rosemary in olive oil before drizzling perfumes every crevice.
Sheet-pan smash: using the bottom of a sturdy mug gives consistent ½-inch thickness for even browning.
Finish hot: a final blast under the broiler caramelizes the herbs and garlic without burning.

Ingredients You'll Need

The ingredient list is short, so quality matters. Look for baby Yukon Gold or Dutch yellow potatoes that are roughly 1½–2 inches across; their thin skins and naturally buttery flesh crisp beautifully while staying creamy inside. Avoid red bliss—they’re too waxy and refuse to fluff. Kosher salt is non-negotiable for the brine; its larger crystals season evenly without over-salting. A pinch of baking soda is the secret weapon: it raises the pH of the water, breaking down potato-cell walls so the exterior turns into a cratered moonscape once roasted.

For the herb oil, I blend extra-virgin olive oil with a tablespoon of clarified butter or ghee; the milk solids in clarified butter add nutty flavor while the oil keeps the smoke point high. Use fresh rosemary—woodsy and resinous—and thyme for citrusy lift. Garlic slices go in cold so they slowly blond, infusing the fat without the bitter bite that minced garlic can give when it burns. Finish with flaky sea salt and a crack of rainbow peppercorns for floral heat.

If you’re dairy-free, swap the clarified butter for more olive oil or avocado oil. Vegan? The recipe already is. Gluten-free guests? You’re golden. For a smoky twist, add ½ teaspoon smoked paprika to the cornstarch. Prefer lemony brightness? Swap thyme for oregano and finish with zest.

How to Make Crispy Smashed Potatoes with Garlic and Herbs for a Side

Brine & Boil

Fill a Dutch oven with 2 quarts cold water, ¼ cup kosher salt, and ½ teaspoon baking soda. Add 2 lb baby Yukon Gold potatoes, bring to a boil, then simmer 15 min until a paring knife slides in with zero resistance. Drain and let steam-dry in the colander for 3 min so the skins wrinkle—those wrinkles become crunch later.

Preheat & Prep Pan

Place a rimmed 13×18-inch sheet pan on the middle rack and heat oven to 450 °F. A screaming-hot surface ensures immediate crust formation; no parchment needed—the potatoes won’t stick once the fat hits.

Cornstarch Coat

Transfer potatoes to a bowl, sprinkle 1 tablespoon cornstarch, and gently tumble. The starch grabs onto the residual moisture, creating a micro-layer that dehydrates instantly in the oven for glass-shard crispness.

Smash Strategy

Remove the hot pan, add 2 tablespoons olive oil–ghee blend, swirl to coat. Space potatoes 2 inches apart. Using the flat bottom of a sturdy coffee mug, press each potato to ½-inch thickness; twist slightly so the skin fractures but the flesh stays intact. Work quickly so the pan stays hot.

First Roast

Slide pan back onto the middle rack and roast 20 min. Resist the urge to flip early; undisturbed contact yields the deepest Maillard browning. The undersides will turn golden and lacey where potato meets fat.

Herb Oil Infusion

While potatoes roast, combine remaining 3 tablespoons olive oil, 2 rosemary sprigs, 4 thyme sprigs, and 3 thinly sliced garlic cloves in a small skillet. Warm over medium-low 4 min until garlic is fragrant and just turning blond. Remove from heat; the residual heat finishes the job without bitterness.

Flip & Baste

After 20 min, flip potatoes with a thin metal spatula. Drizzle half of the warm herb oil over the tops, letting it seep into crevices. Return to oven 12–15 min until second side is equally bronzed.

Broiler Finish

Move pan to upper third, switch oven to broil. Broil 2–3 min until herbs crisp and garlic curls. Watch like a hawk; the line between toasted and torched is 30 seconds.

Season & Serve

Transfer potatoes to a warm platter, spoon remaining herb oil over top, shower with flaky sea salt, cracked rainbow pepper, and optional lemon zest. Serve immediately—crispy waits for no one.

Expert Tips

HOT PAN, COLD OIL

Heating the empty sheet pan mimics a cast-iron skillet, creating an instant sear. Add oil only after the pan is hot to prevent sticky polymerization.

MUG VS. GLASS

Use a ceramic coffee mug with a flat bottom; glass can shatter from thermal shock, and ridged measuring cups leave uneven surfaces.

DRY = CRUNCH

After boiling, let potatoes steam in the colander until the skins look matte. Any surface moisture steams instead of crisps.

NO CROWDING

If doubling, use two pans. Overlapping potatoes trap steam and you’ll end up with soggy bottoms—nobody wants that.

MAKE-AHEAD TRICK

Boil and smash potatoes up to 24 hrs ahead; refrigerate on a parchment-lined tray, uncovered. Roast from cold—add 5 extra min.

COLOR CODE

Golden brown is flavor; deep mahogany is bitter. If edges darken too fast, lower oven 25 °F and extend time.

Variations to Try

Spicy Harissa: Whisk 1 tablespoon harissa paste into the herb oil and finish with preserved-lemon zest.
Loaded Baked: Top hot potatoes with shredded cheddar, crispy bacon, chives, and a dollop of sour cream.
Asian Umami: Replace cornstarch with rice flour, swap rosemary for Thai basil, and finish with tamaki glaze and sesame seeds.
Parmesan Truffle: Add ¼ cup grated Parm to the cornstarch toss and drizzle with white-truffle oil after roasting.
Smoky Paprika & Lime: Add 1 teaspoon smoked paprika to the starch and finish with lime zest and cilantro.

Storage Tips

Refrigerate: Cool completely, then store in an airtight container up to 4 days. Reheat on a sheet pan at 425 °F for 8–10 min to restore crunch—microwaves turn them rubbery.

Freeze: Freeze smashed, pre-roast potatoes on a tray until solid, then transfer to a zip bag for up to 2 months. Roast from frozen, adding 10 extra min.

Make-Ahead: Boil and smash up to 24 hrs ahead; keep uncovered in the fridge so the skins dry out. Roast when ready to serve.