Special equipment: 4 (10-ounce) ramekins, each 2 1/2 inches tall and 3 1/2 inches in diameter.
Place an oven rack in the center of the oven. Preheat the oven to 425 degrees F. Spray 4 (10-ounce) ramekins with vegetable oil cooking spray. Set aside.
For the filling: In a medium bowl, mix together the pineapple chunks, apricots, cinnamon, arrowroot, and reserved pineapple juice. Divide the mixture equally between the ramekins.
For the topping: In a food processor, combine the flour, oats, butter, sugar, pecans, and salt. Pulse together until the butter is the size of peas.
Spoon the topping over the filling mixture. Place the ramekins on a small baking sheet and bake until golden and the filling is bubbling, 18 to 20 minutes. Cool for 10 minutes and serve.