Sweet Potato Gratin | KTA Super Stores

Ingredients

• 2 lb sweet potatoes (washed)
• 2 Tbsp olive oil
• 4 Tbsp butter (divided)
• 1 cup sweet onions (diced small)
• 1 Tbsp garlic (minced)
• 1 qt heavy whipping cream
• 2 Tbsp chicken base or bouillon
• salt
• pepper
• 7 slices Gruyere Swiss cheese
• 1 cup parmesan cheese
• green onion (thin sliced)