• Preheat oven to 350° F.

Apple filling

• In a large bowl, toss together sliced apples, cinnamon, nutmeg, sugar, and flour. Add rum and stir to combine. Pour the apple mixture into a 9x13 inch baking dish.

Streusel topping

• In a medium bowl, mix together flour, brown sugar, rolled oats, cinnamon, and nutmeg. Add melted butter and stir to combine until crumbly. Evenly spread streusel topping over the apple filling.
• Bake uncovered for 50-60 minutes or until bubbly and the apples are tender.

Rum caramel

• While the apple crisp is baking, make the rum caramel. Heat the sugar in a small saucepan over medium heat, stirring constantly just until the sugar melts into a thick brown liquid, about 5-7 minutes.
• Add the butter once the sugar is completely melted; bubbling will occur. Whisk until melted and mostly combined, about 1 minute.
• Slowly add the heavy whipping cream while whisking; more bubbling will occur. Let the caramel boil for about 30-60 seconds until it rises in the pan. Remove from heat and quickly whisk in the rum and salt.
• Once the apple crisp has finished baking, drizzle half of the rum caramel over the apple crisp in the pan. Reserve the remaining rum caramel for drizzling over individual servings.