Place the roasted red peppers in a food processor or blender and process until completely smooth; set aside.

In a large skillet or saucepan over medium heat, melt the unsalted butter until foaming.

Add the minced garlic to the butter and sauté for 60 seconds until fragrant but not browned.

Pour in the heavy cream and whisk to combine with the butter and garlic.

Bring the cream mixture to a gentle simmer, then reduce heat to low and cook for 5 minutes, stirring occasionally to prevent scorching.

Whisk the roasted red pepper purée into the cream mixture until the color is uniform.

Gradually add the grated Parmigiano-Reggiano cheese, one handful at a time, whisking constantly until the cheese is fully melted and the sauce is emulsified.

Season with salt, white pepper, and red pepper flakes.

Continue to cook on low heat for 2-3 minutes until the sauce achieves the desired thickness to coat the back of a spoon.