Step 1

Heat oil in a 10-inch skillet over medium-high heat. Add thinly sliced onions, thinly sliced zucchini, chopped red peppers, and salt. Cook for 8 minutes, stirring occasionally until the vegetables are slightly tender.

Step 2

Stir in chopped tomatoes, minced garlic, Italian seasoning, salt, and pepper and cook, stirring occasionally, 3 minutes.

Step 3

Transfer the ratatouille to a bowl or a plate and top with grated or shredded Parmesan cheese, if desired.