Luxe French Potatoes

Place rack in middle of oven and preheat to 350°F. Place potatoes in a large wide heavy pot. Add 1 1/2 tsp. salt and enough cold water to cover by 2". Bring to a boil over high heat, then reduce heat to medium-low and simmer until potatoes break apart when pierced with the tip of a knife, 35–40 minutes.

Meanwhile, cook garlic, cream, and butter in a medium saucepan over medium heat, whisking occasionally, until butter is melted. Whisk in nutmeg, pepper, and 1 Tbsp. plus 1 tsp. salt. Remove from heat.

Drain potatoes and immediately pass through potato ricer into a large bowl. Stir in cream mixture until smooth.