Easy Root Vegetable Stew

Ingredients

• 1 tablespoon oil
• 1 tablespoon butter
• 1 small onion, chopped
• 2 medium potatoes, peeled and diced
• 2 carrots, peeled and sliced
• 1 celery rib, sliced
• 3 apples, peeled and chopped
• black pepper
• 2 cups water
• 4 large chicken bouillon cubes
• 1 teaspoon ground sage
• sour cream