Roasted Sweet Potato, Gruyère, and Caramelized Onion Quiche – Garden & Gun

Ingredients

• 1 Midway Bakery All-Butter Pie Crust (ingredients below)
• 1 medium sweet potato (about 9 oz.), peeled
• 1 tbsp. canola oil
• Kosher salt to taste
• Freshly ground black pepper to taste
• 1 tbsp. unsalted butter
• ½ sweet onion, thinly sliced
• 1–2 tbsp. white wine for deglazing
• 1 cup (4 oz.) shredded Gruyère cheese
• 6 large eggs
• 1 cup half-and-half
• ¼ tsp. iodized salt
• ¼ tsp. freshly ground black pepper
• Pinch cayenne pepper (optional)
• 1 cup all-purpose flour
• ½ cup (1 stick) cold unsalted butter, cut into small pieces
• ½ tsp. cider vinegar
• 2½–4 tbsp. cold whole milk