Drain potatoes and pour potatoes back into saucepan used to cook them. Smash potatoes over low heat until chunks of potatoes remain, but the majority of the potatoes are smooth. Add the melted butter and half and half mixture to potatoes. Continue to mash the potatoes to incorporate the half and half mixture. Then, mix in garlic, sour cream, bacon crumbles, and cheddar cheese with a spoon until well-combined. Stir in salt and pepper.
In a medium saucepan, melt butter, add half and half and roasted garlic. Heat until simmering.
Place potatoes into large saucepan and add enough water to cover, plus about 1 inch. Cook over medium-low heat until fork tender, about 15-20 minutes.