Trim and thinly slice green onions on an angle. Halve grapefruit across equator. Starting 1/2" in from edge, slice baguette lengthwise on a 45 degree angle, stopping 1/2" from bottom. Cutting all the way to the bottom can cause leakage, so make sure you leave 1/2"! Repeat on other side and remove bread with your fingers. Hollowing bread out in a "V" shape allows egg mixture to bake upwards. On a separate cutting board, cut bacon into 1/2" pieces.

Line a plate with a paper towel. Place bacon in a large non-stick pan over medium heat (no need to preheat) and cook 5-8 minutes, stirring occasionally, or until crisp. Remove to towel-lined plate, discard bacon grease, and wipe pan clean. Place bacon grease in a heat-safe container and discard after it has cooled - never down the sink!

Whisk together milk, eggs, 1/2 tsp. salt, and a pinch of pepper in a medium mixing bowl. Stir in cheese, bacon, and green onions (reserve pinches of bacon and green onion for garnish).

Place hollowed-out bread onto prepared baking sheet. Carefully pour egg filling into bread. Bread will slowly soak up liquid, so add in small increments to prevent overflow. Bake 25-28 minutes, or until eggs are lightly browned on top and no longer jiggle. Remove from baking sheet and let rest 5 minutes.

While boats bake, return pan used to cook bacon to medium-high heat. Add sugar and 1 Tbsp. water and bring to a simmer. Add grapefruit halves, cut side down. Cook 3-5 minutes, or until liquid has evaporated and cut sides appear slightly caramelized. Remove from pan.

Serve egg boat on a plate with candied grapefruit half, or slice boat into 1" pieces if desired. Garnish with reserved green onions and reserved bacon.