Slice 2 Bartlett pears in half, brush with melted butter and place skin side down on the grill for 20 minutes. Make a crispy topping by combining 1/2 cup flour, 1/4 cup white sugar, 1/4 cup brown sugar, 3/4 teaspoon ground cinnamon, 1/4 teaspoon nutmeg, 1/3 cup rolled oats, add 6 tablespoons cold butter and cut all together with a fork or by hand. When pears are starting to get tender, sprinkle crispy topping on the pears for the last 10 minutes of grilling time. Meanwhile, brush fresh flour tortillas with melted butter and grill 2 minutes each side. Remove from grill, brush a little butter on 1 side and sprinkle with cinnamon sugar. When cooled, cut tortillas in quarters to be served later. Remove pears from grill, placing each pear in a single serving bowl with a dollop of vanilla ice cream surrounded by cinnamon tortilla chips. Serve immediately.