I made this for the first time on a Tuesday night when I had a bag of Yukon Golds that weren’t going to last much longer and two leeks looking sad in the crisper drawer. Didn’t expect much. Ended up eating half the pan standing over the sink.
It’s a gratin, basically — potatoes layered with softened leeks, a little cream and broth, and a serious amount of gruyère on top. The toaster oven does something really nice here because the heat is so concentrated. The edges of the potatoes get properly crispy while the middle stays creamy. You get both textures in every bite, which is exactly what you want. The brown butter drizzle before broiling sounds fussy but it takes about two minutes and makes the whole thing taste like you know what you’re doing.
You don’t need much equipment. A small baking dish, a skillet for the leeks, and a toaster oven-safe baking dish that actually fits inside your machine — check the dimensions before you start, because I’ve definitely pulled out a dish mid-recipe only to realize it doesn’t fit. A reliable toaster oven with a working broil setting is the only other real requirement. Most countertop models handle this just fine.
This works as a main course with a simple green salad, or as a side dish for a bigger meal. Feeds four generously, or two people who are actually hungry. It reheats well, which is more than I can say for a lot of toaster oven recipes.
Toaster Oven Crispy Brown Butter Roasted Potato and Leek Soup Gratin
Thinly sliced potatoes and sweet leeks roasted until golden in a toaster oven, then finished with gruyère and a drizzle of brown butter. It's somewhere between a gratin and a soup — deeply savory and surprisingly easy.
Ingredients
For the gratin
Instructions
-
Preheat your toaster oven to 400°F. Use the bake setting, not broil — you'll switch to broil at the very end.
-
Lightly grease a small baking dish that fits your toaster oven (an 8x8 or similar works great). If you're not sure your dish fits, measure first.
-
Heat 1 tablespoon of the butter and all the olive oil in a small skillet over medium heat on your stovetop. Add the leeks, garlic, and thyme. Cook, stirring occasionally, for about 6 minutes until the leeks are softened and just starting to turn golden at the edges. Season with a pinch of salt.
-
Whisk together the vegetable broth and heavy cream in a small bowl. Set aside.
-
Layer half the potato slices in the prepared dish, overlapping them slightly like shingles. Spoon half the leek mixture over the top. Sprinkle with about ⅓ cup of the gruyère, a pinch of salt, and some pepper. Repeat with the remaining potatoes and leeks.
-
Pour the broth and cream mixture evenly over the whole dish. Press the potatoes down gently with a spatula — you want them to absorb the liquid as they cook.
-
Cover tightly with foil and roast for 20 minutes. The potatoes should be mostly tender when you poke them with a knife.
-
While that's going, brown the remaining 2 tablespoons of butter in a small saucepan over medium heat. Swirl it and watch it. It'll foam, then go quiet, then smell nutty. That's the moment. Pull it off the heat immediately.
-
Remove the foil from the gratin. Scatter the remaining gruyère over the top and drizzle the brown butter over everything.
-
Switch your toaster oven to the broil setting and broil for 4 to 6 minutes, watching closely, until the cheese is deeply golden and bubbling in spots. Every toaster oven runs a little different, so start checking at 4 minutes.
-
Let it sit for 5 minutes before serving — it's molten underneath and needs a moment. Scatter parsley over the top and serve straight from the dish.
Notes
Leeks hide a lot of dirt between their layers. Slice them first, then submerge in a bowl of cold water and swish around. The grit sinks, the leeks float. Easy.
Yukon Golds are genuinely the best potato here — they hold their shape but get creamy inside. Russets get a little grainy.
If your toaster oven runs hot (a lot of them do), drop the roasting temp to 375°F and add 5 minutes to the covered cook time before broiling.
Leftovers reheat well. Cover with foil and warm at 350°F for about 10 minutes. The cheese gets a little chewier but it's still good.
Nutrition
Rate this recipe
Made it? Tap a star to rate.
Written by
Emma is a home cook who loves coaxing big flavor out of a toaster oven — from crispy roasted vegetables to easy weeknight dinners and sweet treats. She develops and tests Toastera's recipes for small-appliance kitchens.
Free: the Toaster Oven Cheat Sheet
Get the printable cheat sheet (temps, cook times & safety tips) plus new recipes. No spam, unsubscribe anytime.
