Preheat oven to 375 degrees
Boil a large pot of water
Add potatoes and allow them to boil for 8 minutes
Drain potatoes
In a large saucepan melt butter
Sauté garlic and onion for 2-3 minutes or until tender
Add heavy cream
Add seasoning salt, black pepper , and thyme - stir well
Allow it to cook 4-5 minutes while stirring
Remove from heat
In a large deep cast iron skillet or deep baking dish spray non stick spray
Add a layer of the seasoned cream mixture
Add a layer of potatoes
Sprinkle Gouda and Colby Jack cheese
Spoon over some of the cream mixture
Add another layer of potatoes
Add seasoned cream mixture
Sprinkle remaining Gouda and Colby Jack cheese
Bake for 35-45 minutes
Remove from oven and allow it to sit for 10 minutes
Serve and enjoy!