01 -
Preheat oven to 450°F (232°C).
02 -
Melt butter in an oven-proof skillet over medium heat. Add onion and cook until the edges begin to brown, approximately 5 minutes.
03 -
Add garlic and cook for 1 minute. Pour in the heavy cream and let it simmer until bubbly and slightly thickened.
04 -
Slowly stir in the Parmesan cheese until fully combined.
05 -
Add the sliced zucchini and yellow squash to the skillet. Cook for 4-5 minutes, stirring occasionally.
06 -
Sprinkle the shredded smoked Gouda evenly over the top. Transfer the skillet to the oven and bake for 15-20 minutes, or until the cheese is golden brown.