Mashed Potatoes with Roasted Garlic and Caramelized Onions

Finished bowl of mashed potatoes on a striped dish towel with a spoon and a bulb of garlic in the background

Mashed Potatoes with Roasted Garlic and Caramelized Onions

Soft, buttery mashed potatoes with roasted garlic and caramelized onions blended right in. A simple upgrade that makes a classic side feel a little more thoughtful.

I’ve included both a full version and a scaled-down version for two below.

5 from 1 vote

Print Recipe Pin Recipe

Prep Time 15

Cook Time 25

Total Time 40

Course Side Dish

Cuisine American

Servings 6 servings

Calories 245 kcal

Ingredients

1 whole bulb roasted garlic
2 tablespoons olive oil divided
1 medium onion chopped
1 tablespoon kosher salt for the potato water
4 medium Russet potatoes peeled and quartered
¼ cup butter softened
¼ cup sour cream
¼ cup grated Parmesan cheese
¼ to ½ cup whole milk
Salt and pepper to taste

Instructions

Heat 1 tablespoon olive oil in a large skillet over medium-low heat. Add chopped onion and cook, stirring occasionally, until golden brown and caramelized, about 20–25 minutes.
Transfer the onions to a food processor. Squeeze in the roasted garlic and add a small drizzle of olive oil. Process until smooth. Set aside.
Place potatoes in a large saucepan. Add kosher salt and enough water to cover. Bring to a boil, then reduce heat and simmer until fork-tender, about 15–20 minutes.
Drain potatoes and return them to the pot.
Add a splash of milk and the butter. Mash until desired consistency is reached, adding more milk as needed.
Add the onion-garlic mixture, sour cream, and Parmesan cheese. Stir until the cheese has melted and everything is combined.
Season with salt and pepper to taste. Serve warm.

Notes

When It's Just the Two of Us

1 large Russet potato, peeled and quartered
½ small onion, chopped
½ bulb roasted garlic
2 tablespoons olive oil (use as needed for the onions and garlic)
2 tablespoons butter, softened
2 tablespoons sour cream
2 tablespoons grated Parmesan cheese
2–4 tablespoons whole milk
Salt and pepper to taste

Note: Everything else stays the same—you’re just using a smaller pot and adding milk at the end until the texture is right.

If you have half a head of roasted garlic left, don’t toss it—I’ll usually spread it on toast, stir it into eggs, or add it to whatever I’m cooking later in the week.

Nutrition Facts

Approximate per serving — based on 6 servings

Calories	245
Fat	11g
Saturated Fat	6g
Carbohydrates	32g
Fiber	3g
Sugar	3g
Protein	5g
Sodium	480mg

Nutrition values are estimates and may vary based on ingredients used. If you’re making the version for two, values will adjust based on portion size.

Keyword caramelized onion mashed potatoes, holiday mashed potatoes, mashed potatoes with roasted garlic and caramelized onions, roasted garlic mashed potatoes, special occasion mashed potatoes