Step 1

Arrange a rack in the middle of the oven, remove any racks above that rack, and heat to 350°F. Coat a 2-quart soufflé dish or (8x8xbaking dish generously with butter; set aside.

Step 2

Fill a large saucepan halfway with water, season generously with salt, and bring to a boil over medium-high heat. Add the carrots and simmer, reducing the heat as needed, until very tender, 10 to 12 minutes. Drain well.

Step 3

Place the milk, eggs, and salt in a food processor fitted with the blade attachment or blender and process or blend until smooth. Add the cooked carrots and butter and process or blend until very smooth. Transfer to a large bowl.

Step 4

Add the cheese, flour, and baking powder and stir until combined. Transfer to the prepared dish and spread into an even layer. Bake until puffed and just set in the middle, about 1 hour in a soufflé dish, 45 to 50 minutes in the baking dish. Serve immediately.