Preheat oven to 375 degrees.
Place millet, 2 cups broth, carrot, onion and thyme sprig in a small saucepan.
Bring to a boil, then reduce heat to low and cook, covered for 25 minutes.
Check after 20 minutes and add more broth as needed. Remove from heat and gently stir in chopped tomatoes and black beans.
Spoon into red bell pepper halves.
Pour 1/2 cup broth into a square baking pan or pie pan.
Place stuffed peppers in pan.
Cover with foil and bake for 1 hour.
To serve, spoon Roasted Red Pepper Pesto on top.