How to Make It
Drain the raspberries in a strainer set over a bowl. Peel the apples and rub them with 1 tablespoon of the lemon juice. Quarter and core the apples, then slice them crosswise 1/4 inch thick.
In a heavy nonreactive saucepan, toss the apples with the remaining 1 tablespoon lemon juice. Add the drained raspberry syrup, cover and cook over moderately low heat for 10 minutes. Gently stir the apples, cover and cook for 5 minutes longer. Uncover and simmer, stirring occasionally, until just tender, about 5 minutes. Stir in the raspberries and remove from the heat.
In a large bowl, rub together the oats, sugar, butter and cinnamon.
Preheat the oven to 350°. Spread the apple mixture in a 10-inch ceramic baking dish. Sprinkle the oat topping in a wide ring over the apples and bake for 30 to 35 minutes, or until the oats are toasted and the apples are bubbling around the edges. Serve warm with whipped cream or frozen yogurt.