Add the olive oil to a skillet over medium high heat. Add the onion and sauté for 5 minutes, stirring occasionally. It's ok if it lightly browns.

Add the mushrooms, garlic, and Italian seasoning. Continue to cook, stirring occasionally, for another 5 minutes.

Stir in the Dijon mustard and white wine. Let it bubble for a minute or so.

Add the cream and gnocchi. Wait until it starts to bubble again, then cover the pan and reduce the heat to medium-low. Cook for 3 minutes.

Stir in the spinach, cover the pan again, and cook for 3 minutes.

Stir in the parmesan and season with salt & pepper. Give it a taste; gnocchi should be soft. If not, continue to cook for another few minutes. Garnish with fresh parsley. Serve immediately with more parmesan cheese grated over top if desired.