Crockpot Cheesy Mashed Potatoes with Caramelized Onions

Ingredients

• 2-4 cloves garlic
• kosher salt and black pepper
• 8 sage leaves
• 1 1/2 cups shredded gruyere cheese
• 1-2 yellow onions, thinly sliced or chopped
• 1/2 - 1 cup heavy cream
• 2 cups water
• 5 pounds Russet or Yukon Gold potatoes, peeled and quartered
• 1/4 cup dry white wine
• 2 teaspoons kosher salt
• 1 stick salted butter
• 1/2 cup sour cream
• 1 tablespoon chopped fresh thyme