Preheat oven to 350 F.

In a medium saucepan over medium-low heat, saute onion until soft. Add tomatoes, black beans, cumin, and garlic powder, and simmer until warmed and fragrant. Dust with flour to help set, stir, and allow to thicken for a few minutes.

In another medium saucepan, make the scrambled eggs. Melt 1 tablespoon butter over medium-low heat, then crack eggs into pan and break up yolks with a wooden spoon. Stir constantly, taking the pan off the heat for a moment if the eggs are cooking too fast. Once eggs are set and still creamy-looking, remove pan from the heat.

To assemble the enchiladas, microwave tortilla shells for 10 seconds, to make them more pliable. Coat the bottom of a 13 by 9-inch oven-safe dish with a ladle of enchilada sauce.

Into each flour tortilla, spoon one scoop of black bean filling and one scoop of scrambled eggs. Fold over filling, and place enchiladas in dish with seam side down. Repeat for all 8 tortillas. Top with remaining enchilada sauce and cheese.

Bake for 15 minutes, or until cheese melts.

Garnish with chopped green onion, halved cherry tomatoes, and slices of avocado.