Fill a large pot with salted water and bring it to a rolling boil. Cook the orecchiette pasta according to package instructions until al dente, usually about 9-11 minutes.

In a skillet, heat a drizzle of olive oil over medium-high heat. Add the crumbled Italian sausage and diced onion; cook until browned and the onion is translucent, about 8-10 minutes.

Reduce heat to medium, stir in minced garlic and Dijon mustard; cook for about 30 seconds.

Pour in the dry white wine and simmer for 1-2 minutes until reduced by half.

Add fresh baby spinach and stir until just wilted, about 1-2 minutes.

Add drained orecchiette to the skillet; toss to combine. Add reserved pasta water as needed to reach desired consistency.

Plate the dish and garnish with freshly grated Parmesan cheese if desired.