Sauté the Meat and Aromatics. Turn the Instant Pot to “Sauté” mode and heat the olive oil. Add ground beef or sausage and cook until browned, breaking it apart with a spoon. Stir in onions and garlic, cooking until fragrant.
Add the Sauce and Pasta. Pour in crushed tomatoes, tomato sauce, Italian seasoning, salt, black pepper, and red pepper flakes (if using). Stir well. Add the pasta and water (or broth), ensuring the pasta is fully submerged but not stirred.
Pressure Cook. Close the lid and set the Instant Pot to “Pressure Cook” or “Manual” mode on high pressure for 4 minutes. Once the time is up, do a quick release to prevent overcooking the pasta.
Stir and Add Cheese. Remove the lid and stir the pasta. Dollop in ricotta cheese and mix slightly for a creamy texture. Sprinkle mozzarella and Parmesan cheese over the top, then close the lid for 2-3 minutes to let the cheese melt.
Serve and Enjoy. Garnish with fresh basil or parsley, serve warm, and enjoy your homemade Instant Pot Baked Ziti.