Line a heavy large baking sheet with parchment paper and set aside. Unroll crescent dough; separate along dough perforations into 16 triangles. Overlap 8 dough triangles on prepared baking sheet, positioning longest points in center and forming a 10-inch-diameter dough disk. Press edges of triangles together to seal.

Using a rolling pin, roll out almond paste between 2 sheets of waxed paper into a 9-inch diameter disk. Place almond disc atop dough disk. Spread jam over almond paste . Using remaining 8 dough triangles, arrange second 10-inch diameter dough disk atop jam. Pinch edges of dough disks to seal. Tuck edges under. Bake for 25 minutes, or until golden brown. Remove from oven and cool for 10 minutes.

While ring is baking, make glaze by stirring powdered sugar, water, and almond extract together in a medium bowl until smooth. Drizzle half of glaze over warm crescent. Let glaze set for 10 minutes and then drizzle remaining glaze over. Decorate with sugar-dipped cherries and small pears, if desired.