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Boneless chicken thighs bake over a pile of sliced leeks and yellow potatoes in this easy to assemble casserole-style dinner. As the chicken cooks with Dijon mustard, thyme and white wine, the chicken-fatty juices create a flavorful sauce that cooks the vegetables underneath to perfect fork-tenderness.

Baked chicken thighs with a golden-brown crust, surrounded by diced potatoes and sliced leeks in a white roasting dish. A serving spoon lifts one piece, displaying the tender chicken and vegetables.

The other night I opened the fridge and realized there wasn’t much of a plan for dinner. Even as a recipe developer, that happens more often than you’d think — usually because grocery shopping just didn’t happen.

The creative spark behind this recipe came when my significant other peeked inside and spotted a produce bag of leeks and a package of chicken thighs. Since I almost always have Dijon mustard, thyme and vegetables like leeks or shallots around (they last more than a week in the fridge), this simple baked chicken came together on the fly.

The only step to take your time with is slicing the leeks — but it’s so worth it. Cutting them into thin matchsticks helps them to literally melt into a super delectable texture. Some strands collapse into the pan juices while others turn golden and crisp at the edges.

Karen’s ingredient notes

Ingredients on a light surface: raw chicken thighs on a plate, whole leeks, baby potatoes, sliced shallots, fresh herbs, white wine, Dijon mustard, and a bowl of chicken broth.

Chicken thighs: If you’ve been cooking with me for a while, you already know that I’ve tested and developed dozens of recipes using chicken thighs. I usually prefer them for baking and roasting because they stay juicy and tender, and their additional fat always brings something extra to the plate.
Leeks: I can’t sing enough praises for leeks. Although they’re related to onions, their flavor is more delicate — “more of a whisper than a shout,” as the wonderful food writer Deborah Madison once put it. As they cook, they collapse into soft strands that add sweetness and depth to the whole dish. Shopping tip: The freshest bunches at the grocery store will have upright green tops and their roots still attached.
Yellow potatoes: Potatoes are perfect companions to leeks (I celebrated the combo in this comforting recipe for leek and potato soup with roasted garlic cloves). I paired them with the chicken and leeks in this dish to make it a one-dish dinner you can realistically make on a busy weeknight.

Getting started

Seasoning the chicken: Toss the chicken thighs in a bowl with Dijon mustard, fresh thyme, white wine and red pepper.
Slice the leeks: Remove the tough green upper leaves and the root ends (you can add to your stock pot or compost). Slice the white and light green sections in half lengthwise. Separate the inner and outer sections so they can easily lay flat on the cutting board. Slice lengthwise into thin strips.

Combine the sliced leeks and potatoes in a baking dish. Arrange the chicken thighs on top.
Bake about 30 minutes until the chicken is browned top and the potatoes are fork tender. Some of the exposed leeks will be crisp and caramelized — my favorite part!

This is Delicious , I replaced Thighs with Lightly Flour Coated and cooked Chicken Cutlets as Hubby doesn’t like Thighs at All. I used Bag of Sliced Leeks and 2 Slices Butter in the Sauce. Followed Rest of recipe. Served Over Basmati Rice .