Step 1

In a large skillet, melt butter over medium heat. Add onion and cook, stirring often, until translucent (about 3 minutes). Add garlic and cook an additional 2 minutes, stirring often.

Step 2

Heat the milk in a microwave for 25 seconds; whisk in the cornstarch. Pour mixture to skillet.

Step 3

Add salt, pepper, cream cheese, and Parmesan cheese to skillet; whisk until well combined.

Step 4

Stir in the spinach, coating the spinach completely in the cream mixture. Serve warm.