01 - Heat olive oil in the pressure cooker on sauté mode. Add chopped onion and cook for 2 minutes until softened. Stir in minced garlic and cook for an additional 30 seconds.
02 - Add dried pasta, water or broth, salt, dried oregano, dried basil, and marinara sauce to the pressure cooker. Stir to combine, ensuring the pasta is mostly submerged in the liquid.
03 - Gently add cherry tomatoes and baby spinach on top of the pasta mixture without stirring.
04 - Secure the lid of the pressure cooker and set to high pressure. Cook for 5 minutes.
05 - Perform a quick pressure release according to your pressure cooker's manufacturer instructions.
06 - Stir the pasta thoroughly to ensure even distribution. If the sauce appears thin, set the pressure cooker to 'keep warm' mode and let it sit uncovered for 2-3 minutes to thicken.
07 - Top with grated cheese before serving, if desired.