Preheat the oven to 450 degrees F. Heat a 9-inch cast-iron skillet in the oven.
Add the flour, pears, baking powder and salt to a food processor. Pulse 2 to 3 times to combine. Add 5 tablespoons butter, pulsing until it resembles a coarse meal. Pour in the half-and-half and 2 tablespoons maple syrup and pulse until just combined. Transfer to a floured work surface and roll the dough into a square about 1/2-inch thick. Using a 2 1/2-inch biscuit cutter (or the rim of a glass works, too), cut 8 biscuits, re-rolling if necessary.
Remove the skillet from the oven and melt the remaining 3 tablespoons butter in the hot skillet. Swirl the skillet to coat the bottom and sides with butter, then pour the butter into a bowl and mix with the remaining 2 tablespoons maple syrup. Add the biscuits to the skillet and brush them each with a little of the maple butter, saving the rest for finishing.
Bake until lightly browned, 8 to 10 minutes. Brush the remaining maple butter on the biscuits and let them cool slightly. Serve warm or at room temperature.
The biscuit dough can be made in a bowl with pastry cutters, knives or your hands instead of a food processor.