Cut the quince paste into 1-inch cubes and roll them in the crushed almonds. Cut the cheese into 1-inch cubes.
Put a quince cube onto a toothpick, then a watercress leaf followed by a cube of cheese. Place on a platter and serve.
Parmigiano-Reggiano can be substituted for the Manchego. Quince paste can be found in cheese shops or Latin markets.