Preheat oven to 375°. In a large skillet over medium heat, cook bacon until crispy, about 8 minutes. Drain bacon on paper towels and leave about 2 tablespoons of fat in skillet. Add asparagus to skillet and cook until asparagus is bright green and only slightly tender. Season with salt and pepper then remove from skillet and squeeze lemon juice on top. Chop bacon and asparagus into bite-size pieces.
Cut brie into small square pieces, about 2” wide.
On a lightly floured surface, unroll crescent dough into a large rectangle. If there are perforated edges, pinch together seams to seal. Cut dough into 24 squares.
Grease a 24-cup mini muffin tin with cooking spray. Place a crescent square into each muffin cup then fill with brie, cooked bacon, and asparagus.