Choose richly colored papayas that yield slightly to pressure. Amaretto is an Italian liqueur that combines the essences of apricot and almond. This dish can be refrigerated for up to one week.
Preheat oven to 375F.
Combine rice syrup, lemon juice, sugar and cinnamon sticks in heatproof baking dish. Heat over medium-high heat, 1 minute. Add sliced papaya, pineapple chunks, crushed pineapple with juice and Amaretto. Bring mixture to a boil, stir gently and reduce heat immediately to low. Cook for 15 minutes, top with almonds and sprinkle with ground cinnamon.
Place uncovered baking dish in oven. Bake for 25 minutes. Remove from oven, cool, cover and chill overnight in the refrigerator before serving.