Sweet Potato and Gouda Gratin
Ingredients:
- 2 pounds deep orange sweet potatoes (3 or 4 medium total), peeled and sliced 1/8 in. thick
- 1 large shallot, thinly sliced, rings separated
- 2 teaspoons chopped fresh thyme leaves, plus a thyme sprig
- About 1 tsp. kosher salt
- About 1/2 tsp. pepper
- 2 cups (6 1/2 oz.) shredded aged gouda cheese
- 4 tablespoons flour, divided
- 3/4 cup whipping cream
- 3/4 cup reduced-sodium chicken broth or vegetable broth