Bring a large pot of salted water to a boil. Cook the refrigerated ravioli according to the package directions, usually 3–5 minutes, until tender. Reserve about 1/2 cup of the pasta water, then drain the ravioli carefully.

While the ravioli cooks, melt the butter in a large skillet over medium heat. Add the minced garlic and cook for 30–60 seconds, stirring often, just until fragrant without allowing it to brown.

Pour the heavy cream into the skillet and bring it to a gentle simmer. Cook for 2–3 minutes, stirring occasionally, and avoid a vigorous boil.

Reduce the heat to low and whisk in the basil pesto and finely grated Parmesan until the sauce is smooth and creamy.

Add the drained ravioli to the skillet and toss gently until each piece is coated. If the sauce is too thick, add the reserved pasta water 1 tablespoon at a time until it reaches the desired consistency.

Season with salt and freshly ground black pepper. Garnish with chopped basil or parsley and extra Parmesan if desired, then serve immediately.