Potato and Apple Gratin

Ingredients

• 3 to 4 medium russet or Yukon Gold potatoes (about 1 1/2 pounds), well scrubbed and thinly sliced
• 1 1/2 large Cosmic Crisp, Fuji or Granny Smith apples, cored and thinly sliced
• 4 to 5 ounces brie, cut into 1/8 inch slices
• 1 1/2 cups coarsely grated Parmesan cheese
• 1 tablespoon butter
• 3/4 cup chopped sweet onion
• 1/2 large Cosmic Crisp, Fuji or Granny Smith apple, cored, peeled, and chopped (about 3/4 cup)
• 1 teaspoon minced garlic
• 1 cup chicken stock or vegetable stock
• 1/4 lemon
• 1/2 cup heavy cream
• Salt and pepper, to taste