Cook pasta according to package instructions. Be sure to omit the salt.
Heat 1 teaspoon olive oil in a skillet and cook the sausage over medium-high heat until browned. Transfer to a plate.
Add the other 1 teaspoon of olive oil to the same skillet and cook the minced garlic and chopped onion. Cook for about 3 minutes over medium-low heat, until the garlic and onion are soft.
Add the chopped tomatoes, chopped oregano and black pepper. Increase the heat to medium-high and bring to a simmer. Cook at a simmer for about 5 minutes, until the tomatoes start breaking down to a sauce-like consistency.
Toss together the tomato sauce, pasta, grated parmesan cheese, and sausage. Top with chopped fresh basil or oregano.