Preheat oven to 400 degrees. Arrange oven racks to middle and bottom positions. Place a medium, oven-safe non-stick pan or 8"-9" glass or ceramic pie pan on the top oven shelf to preheat. Line a baking sheet with foil. Lay bacon on baking sheet and brush with half of the maple syrup. Sprinkle brown sugar over bacon. Rinse and quarter lemon.

Bake bacon on lower shelf for 16-20 minutes, or until brown sugar has melted and bacon is crispy. Remove bacon from pan and place on two small serving plates. Set plates aside to allow the melted sugar to set and slightly harden on the bacon as it cools.

Whisk milk, liquid egg, and vanilla extract in a bowl until fully combined. Add the flour and granulated sugar and whisk for 1-2 minutes, or until batter is lightened in color.

Using an oven mitt, remove preheated non-stick pan or pie pan from oven and add butter to pan. Swirl butter in pan until fully melted, making sure all sides of pan are buttered. Pour batter into hot pan and place pan on middle rack in oven. Bake for 12-15 minutes, or until edges are brown and pancake puffs, like a popover. (It's normal for the pancake to begin deflating immediately after leaving the oven!)

Sift powdered sugar through wire-mesh strainer over the Dutch Baby. Slice in half and plate each portion. Serve with lemon quarters, remaining maple syrup, and candied bacon.