In a large pot, brown sausage over medium heat until there is no pink. If there are large chunks, break into smaller nickel-sized pieces. Once cooked, pour into a bowl and set aside
While sausage is cooking, chop your onion and spinach. Once sausage has been removed from pan, add 1 teaspoon of oil into pan and cook onion for 1 minute. Add in spinach and cook an additional 3 minutes, or until vegetables are soft.
Add pasta sauce, pesto, red pepper, water, and pasta to pan. Increase heat to high and bring to a boil. Cook according to the package directions for your pasta, stirring occasionally. (Ours was 9 minutes for al dente.)
Add sausage back into the pan and stir until dispersed throughout pasta.
To serve, spoon into bowls or on plates. Top with Parmesan and basil, if using.
Using a tablespoon, scoop a heaping cloud of Ricotta and place it on top of the individual portion of the pasta. Serve immediately.