• Prepare Puff Pastry Sheets: Remove the puff pastry sheets from the freezer and let thaw for 30–60 minutes, until they can be easily rolled out without cracking.
  2 rolled sheets store bought puff pastry
• Caramelize Onions: Melt 1 tablespoon butter in a skillet over medium heat. Add sliced onions and cook, stirring occasionally, for 25-30 minutes. The onions should turn a deep golden color and become sweet.
  2 large onions, 1 tablespoon butter
• Cook Bacon: Cook bacon in a skillet over medium heat until crispy. Remove and place on a paper towel. Reserve the fat in the skillet.
  8 slices bacon
• Fry Sage Leaves: Heat the reserved bacon fat over medium heat. If needed, add a small amount of oil to ensure there’s enough fat to cover the bottom of the skillet.
  15 sage leaves
• Once the fat is hot (but not smoking), test by dipping the edge of a sage leaf into the oil. If it sizzles, the oil is ready.
• Add the sage leaves and fry for 15–20 seconds, or until the leaves are crisp and bright green. Remove the fried sage leaves and place them on a paper towel.
• Make Béchamel Sauce: In a small saucepan, melt the butter over medium heat. Sprinkle in the flour and whisk continuously for 1–2 minutes to form a smooth paste (called a roux). This step helps cook out the raw flour taste.
  1 ½ tablespoon butter, 1 ½ tablespoon all purpose flour
• Slowly pour in the milk while whisking constantly to prevent lumps from forming. Start with a small amount of milk to loosen the roux, then gradually add the rest.
  1 cup milk
• Cook the sauce, whisking often, for 3–5 minutes, or until it thickens to a creamy consistency that coats the back of a spoon. Season with salt, pepper, thyme, and sage to taste. Remove from heat and set aside to cool slightly before assembling the tart.
  salt and pepper, pinch of dried thyme, pinch of dried sage
• Prepare Toppings: Peel and thinly slice the apple. Grate the cheddar cheese.
  1 small apple, 1 cup white cheddar cheese

Assemble the Tart

• Roll out each puff pastry sheet onto a parchment-lined baking sheet. Spread half the béchamel sauce evenly over each sheet. (If the béchamel is too thick to spread, whisk in a small amount of additional milk for a spreadable consistency.)
• Layer with half the caramelized onions, apple slices, and crumbled bacon on each sheet. Sprinkle with white cheddar and goat cheese.
  2 oz goat cheese
• Bake in a preheated oven at 400°F (200°C) for 20-25 minutes, or until the pastry is golden and puffed. (It takes 25 minutes in most ovens.) Remove from the oven and garnish with fried sage leaves and a drizzle of balsamic reduction. Slice and serve warm.
  drizzle of balsamic reduction