Heat oven to 375°, and place rack in middle position. Peel apples and cut into thin slices. Toss with lemon juice, dried cranberries, 1/2 tsp cinnamon, and 1 TBS brown sugar. Divide apple mixture among baking dishes (see note below*). Place dishes on baking sheet, and sprinkle each with 1 TBS of water. Bake uncovered until apples are crisp-tender, about 20 minutes.
While apples are baking, place oats, cinnamon, and remaining brown sugar in small bowl and combine. Add butter to mixture and combine by hand until butter is evenly distributed. Stir in toasted almonds, if desired.
After preliminary baking, remove apples from oven and divide topping among baking dishes. Bake 25-30 additional minutes. Transfer dishes to rack and cool. Serve warm or at room temperature. If desired, cover and refrigerate overnight, and microwave to warm prior to serving. Garnish with Greek yogurt.
*This recipe makes 4 small servings (1/3 cup ramekins) or 2 medium servings (1 cup ramekins)