Cheesy Mexican Hash Brown Casserole

Name: Cheesy Mexican Hash Brown Casserole
Ingredients: 1-3 tablespoons oil; 1/2 large red bell pepper, diced; 1/2 large green bell pepper, diced; 1/2 cup red onion, diced; 3 cups shredded potatoes or frozen hash browns; 1 cup cheddar, shredded; 1 cup taco cheese, shredded (Mexican blend/etc. - separated into halves); 1-2 tablespoons taco seasoning; 1 cup heavy or whipping cream; 1/2 cup sour cream; cooking spray; 1 cup cooked ground beef; salsa, as needed; green onion, thinly sliced, as needed