Place potatoes in a pot, and fill with water until they are just covered. Bring the water to a boil and cook potatoes for approximately 12-15 minutes. You want the potatoes to be soft enough that you can easily poke it with a fork. Remove from heat and drain water.
While the potatoes are cooking, in a saucepan, heat 5 mL butter, and fry garlic until golden brown.
With a potato masher, mash all the potatoes.
Combine the remaining amount of butter, butter garlic sauce, milk, salt and pepper.
Notes
If you want it more creamy, gradually add more milk until you reached your desired consistency.