Preparation Position rack in center of oven; preheat to 375°F. Place nuts in plastic bag; crush coarsely with rolling pin. Transfer to bowl. Mix in sugar, butter, flour and liqueur. Using melon baller, core each pear half, creating cavity. Arrange pears, cut side up, in 11x7-inch glass baking dish. Mound nut mixture in cavities, dividing equally and pressing to compact. Pour apple juice into dish around pears. Drizzle pears with maple syrup. Bake pears until tender when pierced with small sharp knife, basting occasionally with juices, about 45 minutes. Transfer pears to plates. Drizzle with juices.
Preparation Position rack in center of oven; preheat to 375°F. Place nuts in plastic bag; crush coarsely with rolling pin. Transfer to bowl. Mix in sugar, butter, flour and liqueur. Using melon baller, core each pear half, creating cavity. Arrange pears, cut side up, in 11x7-inch glass baking dish. Mound nut mixture in cavities, dividing equally and pressing to compact. Pour apple juice into dish around pears. Drizzle pears with maple syrup. Bake pears until tender when pierced with small sharp knife, basting occasionally with juices, about 45 minutes. Transfer pears to plates. Drizzle with juices.