Begin by washing and chopping your bell peppers, zucchini, and green beans into bite-sized pieces. Aim for uniform sizes to ensure even cooking.

In your Instant Pot, heat a tablespoon of olive oil over medium heat. Add the chopped vegetables and sauté for 5-7 minutes, stirring occasionally, until they become tender and slightly caramelized.

Once the vegetables are sautéed, stir in one can of black beans, along with the garlic powder, onion powder, and paprika. Mix well and fold in your chosen cheese.

Preheat your oven to 350°F (175°C). Carefully pour the vegetable and bean mixture into a greased baking dish, spreading it evenly.

Sprinkle gluten-free breadcrumbs evenly over the casserole mixture. Place it in the preheated oven and bake for 25-30 minutes.

After baking, remove the casserole from the oven and let it rest for about 5 minutes before slicing and serving warm.