Stir together first 5 ingredients; spoon pear filling into a greased 8" square baking dish.
Combine oats and next 4 ingredients; add butter, stirring well. Pinch topping into large crumbs. Sprinkle topping over pear filling. Bake, uncovered, at 375° for 40 minutes or until pears are tender and topping is golden. Let stand 15 minutes. Serve warm with ice cream or unsweetened whipped cream.