Boil ravioli in salted water until just tender. Reserve 1/4 cup pasta water, then drain.
Make Garlic-Herb Butter: Melt butter with olive oil in a skillet over medium heat.
Stir in garlic and red pepper flakes. Cook 30 seconds. Splash in lemon juice and pasta water.
Toss in ravioli. Finish with parsley and Parmesan. Season with salt and pepper. Serve.
Make Tomato-Basil: Warm olive oil in a saucepan. Sauté garlic 30 seconds.
Add crushed tomatoes, oregano, sugar, salt, and pepper. Simmer 6–8 minutes.
Stir in basil and a spoonful of pasta water. Coat ravioli in the sauce. Serve with Parmesan.
Make Brown Butter Sage: Cook butter over medium heat until golden and nutty, 3–4 minutes.
Add sage to sizzle for 15 seconds. Off heat, stir in lemon juice and a little pasta water.
Toss with ravioli. Top with Parmesan. Season lightly with salt and pepper. Serve right away.