Cut the challah into thick slices (about 6 from one loaf), then trim off the excess crust (save it for French toast or bread pudding).
Mix the butter, brown sugar, honey, and vanilla into a smooth compound, then slather it on all sides of the sliced challah.
Arrange the slices on a parchment-lined baking sheet and bake at 360F for 8 to 10 minutes. Flip and bake another 8 to 10 minutes, until deep golden brown but not burnt.
Place the slices on a cooling rack for about 15 minutes; the coating hardens as it sits. Serve with ice cream and warm salted caramel or an extra drizzle of honey.
