Preheat the broiler by positioning your oven rack near the top, about 6 inches from the heating element, and set your oven to medium broil.

Slice the grapefruits in half horizontally and place on a baking pan cut-side up. Drizzle honey over each half.

In a mixing bowl, combine cold unsalted butter, light brown sugar, all-purpose flour, ground cinnamon, nutmeg, and salt to create the crumbly topping.

Evenly sprinkle the crumb mixture over the honey-drizzled grapefruit halves.

Broil the grapefruit halves for about 8-9 minutes until the topping is golden brown and slightly crisp.

Remove from the oven and let sit for a minute before serving. Optionally, add whipped cream or vanilla ice cream.