Turn your Instant Pot to the "Sauté" setting. Once hot, add the olive oil and let it warm up. Add the finely chopped garlic and sauté for about 1 minute until fragrant. Be careful not to burn it!
Add the ground beef to the pot. Break it up with your wooden spoon, and cook until it’s no longer pink. This should take about 5-7 minutes. Sprinkle in the onion powder, Italian seasoning, salt, and black pepper as the meat cooks.
Once the beef is browned, it’s time to layer in the spaghetti noodles. Break them in half if needed, and lay them in a crisscross pattern to avoid clumping. Pour in the water, diced tomatoes, and crushed tomatoes or pasta sauce. Do not stir! Just gently press the noodles down into the liquid.
Close the lid of the Instant Pot and ensure the valve is set to "Sealing." Set it to cook on high pressure for 8 minutes.
When the cooking time is up, carefully perform a quick release by turning the valve to "Venting." Once the pressure has fully released, open the lid and stir the spaghetti gently to combine.
Scoop the spaghetti into bowls and serve hot. You can garnish with freshly grated Parmesan cheese or fresh basil if desired.
