1. In a 9- to 10-inch nonstick, ovenproof frying pan (with sloping sides) over medium-high heat, stir honey and orange juice until boiling. Cook without stirring until mixture is foamy, slightly thickened, and reaches 230° (carefully tilt pan so mixture is deep enough to register on thermometer), 2 to 4 minutes. Chill until thickened, about 15 minutes. Slightly overlap orange slices in concentric circles over syrup.
2. In a large bowl, with a mixer on high speed, beat butter and sugar until smooth. Add eggs one at a time, beating well after each addition. Beat in orange peel.
3. In another bowl, mix flour, baking powder, and salt. Stir half the flour mixture into butter mixture just until incorporated. Stir in milk, then remaining flour mixture, just until incorporated. Carefully scrape batter over orange slices in pan and spread level.
4. Bake in a 350° regular or convection oven until a wooden skewer inserted in the center comes out clean, 35 to 40 minutes for regular, 25 to 30 minutes for convection. Let cool for 5 minutes.
5. Invert a flat plate over pan. Invert cake onto plate and lift pan off, being careful with hot syrup. Let cool completely, then cut into wedges.