Add potatoes to a large saucepan and cover with about 1 inch of water. Salt water and bring to a boil over medium high heat. Once boiling, cook for about 10 minutes or until potatoes are soft and begin to break apart when pierced with a knife. Drain potatoes in a large colander and set aside.
Return the empty pan to the stove and melt butter on low heat. Once the butter is melted add garlic and cook for 2-3 minutes.
Remove from heat and stir in milk and ricotta, salt and pepper. Return the potatoes to the pan and whip with a hand mixer until smooth. Adjust salt and pepper to taste.