Wash sweet potatoes and let air dry completely.

Preheat convection oven to 350 degrees.

Heat bacon grease carefully in microwave until it is barely melted. Using gloves or a basting brush, cover sweet potatoes completely on all sides, then place in foil lined baking sheet. Bake until completely soft, around one hour, then remove from oven and turn oven to low broil.

In a saucepan over medium heat, add the butter, brown sugar and honey, whisking to combine. Cook until it begins to bubble then turn down to low and allow to simmer until thick, about 5 minutes.

Pierce the top of the cooked sweet potatoes in a line from one end to the other and using oven mitts, squeeze ends together, pressing the them open.

Drizzle 1-2 tablespoons of caramel sauce in the bottom of each sweet potato, then pile 1/2 cup of marshmallows on top. Place back in the oven for 2-4 minutes or until the marshmallows are golden and fluffy.