except spinach): Add the chopped onion, broccoli florets, sliced carrots, sliced bell peppers, frozen peas, and cherry tomatoes to the bottom of the slow cooker. Drizzle with the olive oil or melted butter and sprinkle in the garlic, Italian seasoning, dried basil (if using), salt, black pepper, and red pepper flakes.
Add the pasta: Pour the uncooked pasta evenly over the vegetables, but do not stir yet. Keeping the pasta on top helps it cook more evenly and prevents it from getting too mushy.
Mix the liquid and cheese: In
