Bring a large pot of salted water to a boil. Add orecchiette pasta and cook until al dente, about 10-12 minutes. Reserve a cup of pasta water and drain the rest.

In a large sauté pan, melt butter over medium-low heat. Add diced red onion, season with salt and pepper, and sauté until translucent, about 5-7 minutes.

Add minced garlic and cook for 1-2 minutes until fragrant. Stir in tomato paste and cook for about 5 minutes, allowing it to darken.

Pour in vodka, stir to combine, and let simmer for 1 minute until the alcohol evaporates.

Reduce heat to low, stir in heavy cream and red pepper flakes. Allow to simmer for 2-3 minutes until slightly thickened.

Add drained orecchiette to the sauté pan, tossing gently to coat. Add reserved pasta water if the sauce is too thick.

Remove from heat, stir in Parmesan cheese until melted. Adjust seasoning as necessary. Serve garnished with basil leaves.