Preheat the oven to 350°F. Lightly oil an 8x8" glass baking dish with coconut oil.
Wash the potatoes and cut them into thin, circular slices. Place the potatoes in a large mixing bowl. Mix in the chopped onion and crushed garlic.
Slice up the breakfast sausages and toss them into the potatoes.
In a seperate bowl, combine the melted butter, cheese, and yogurt. Stir until combined.
Add the cheese mixture to the potato mixture and stir until everything is thoroughly combined. Transfer the mixture to the 8x8" baking pan and spread it into an even layer.
Add salt and pepper to taste. Cut the tablespoon of cold butter into cubes and place them over the potato mixture.
Bake for 40-45 minutes. The potatoes should be soft and the cheese should be bubbly. Allow the cheesy potatoes to rest for 5 minutes before serving.