Ingredients
1 1/2 pounds carrots, peeled and cut into thick sticks
1 1/2 pounds yellow potatoes (Yukon Gold), scrubbed and cut into 1-inch chunks
6 tablespoons unsalted butter, melted (plus a little extra for greasing the dish)
1 1/2 teaspoons kosher salt
Directions
Preheat your oven to 400°F (200°C). Lightly grease a medium white casserole dish (about 2 to 2.5 quarts) with a small amount of butter to keep the vegetables from sticking and to help them brown.
Prep the vegetables: Peel the carrots and slice them into thick sticks, about 1/2 to 3/4 inch wide and 2 to 3 inches long. Scrub the yellow potatoes well (you can leave the skins on for more texture) and cut them into roughly 1-inch chunks so they cook at the same rate as the carrots.
Combine carrots and potatoes in the greased casserole dish, spreading them out into an even layer so they roast rather than steam. If your dish is very deep, try not to pile the vegetables too high; a shallow layer helps everything caramelize.
In a small bowl or measuring cup, melt the butter in the microwave or on the stovetop. Stir the salt into the melted butter until it’s evenly distributed.
Pour the salted butter evenly over the carrots and potatoes. Use clean hands or a large spoon to toss everything right in the casserole dish until all the pieces are lightly coated and glossy.
Cover the casserole dish tightly with foil and place it on the middle rack of the preheated oven. Bake covered for 25 to 30 minutes, until the vegetables are starting to soften when pierced with the tip of a knife.
Carefully remove the foil (watch out for steam), give the vegetables a gentle stir to re-coat with the buttery juices, and spread them back into an even layer. Return the uncovered dish to the oven.
Continue baking uncovered for 25 to 35 minutes, stirring once more halfway through, until the carrots and potatoes are very tender, the edges are caramelized, and there are golden-brown spots on the vegetables and along the edges of the dish. Total bake time will be about 50 to 65 minutes depending on your oven and the size of the vegetable pieces.
Taste a potato chunk and a carrot stick for seasoning; if needed, sprinkle a small pinch of extra salt over the top and gently toss before serving. Bring the hot casserole dish straight to the table and serve the vegetables with the buttery pan juices spooned over each portion.