Meanwhile, using a vegetable peeler, remove lemon peel in wide strips, avoiding the pith. Thinly slice peel and transfer to a small bowl. Trim both ends of lemon so you can set it upright. Using a sharp knife, cut away lemon rind, exposing flesh. Cut lemon crosswise into ½ » rounds; remove seeds. Finely chop lemon flesh and add to bowl with lemon peel. Add shallots, honey, red pepper flakes, 2 Tbsp. lemon juice, and a 4-finger pinch of salt. Stir in 2 Tbsp. oil; season with black pepper. Let dressing sit until ready to use.