Notes:Guava paste is available in the Latin American aisle of most supermarkets and also in a variety of online stores. In a pinch, quince paste is an acceptable substitute. I used one (17.3-ounce) package of Pepperidge Farm brand frozen puff pastry sheets for this recipe, which contains two puff pastry sheets. Dufour brand frozen puff pastry comes in 14-ounce packages containing only one sheet of puff pastry. If using Dufour you will need two packages, and will get ten pastelitos, rather than eight. Roll the thawed pastry sheets out to 12- by 16-inches. Cut off a 12- by 4-inch strip. Cut remaining 12- by 12-inch piece into four 6-inch squares. Proceed with recipe, but increase guava to 10 ounces and cream cheese to 12 ounces. Fold the square pieces of pastry diagonally into triangles, and fold the two 12- by 4-inch strips in half over the filling to make rectangular pastelitos. Increase baking time to 15 to 20 minutes. Both versions of the recipe may be halved. Adjust oven rack to middle position if doing so.