INGREDIENTS
1
lbs russet (baking) potatoes, peeled and cut into 2-inch pieces
1 lb
parsnips, peeled and cut into 1-inch pieces
3 cloves
garlic
1
sprig rosemary
1/2 tbsp
salt, plus more to taste
1/4 cup
light sour cream
1/4 cup
2% milk
1 tbsp
unsalted butter
black pepper