Preheat oven to 400°F
In a small bowl, using a whisk, combine the egg yolk and cold water. Whisk until combined and set bowl aside.
Take cream cheese out of the package and place on cutting board. Using a large knife, cut the cheese first in half longwise, and then cut each half in six long sticks. There will be twelve total sticks of cream cheese.
To prepare the pastries, flour countertop and take one of the packs of puff pastry out of the box. There will be two sheets per box. Using a rolling pin, roll the sheet to a rectangle that is 8 inches wide by 12 inches. Using a pastry cutter, cut the sheet in half longwise, and on the long side, make two cuts so there will be three pieces. Each sheet will six squares. Taking one square, place one stick of cream cheese on the diagonal. Sprinkle one teaspoon of sugar alongside of the cream cheese. Using a pastry brush, brush the inside corners with the egg wash. Take the diagonal tip and press down. And then pull the other diagonal corner up and stretch to ensure that the corner is underneath the pastry. The finished pastry will have the cheese visible. Place on a parchment lined sheet pan while the rest of the pastries are prepared. When all quesitos are assembled and arranged on the sheet pan, use the pastry brush and brush tops and sides with the egg wash. Using the tines of a fork, poke holes to make “vents” on the quesitos after brushing.
Bake the quesitos for 15-20 minutes, or until the pastries are a deep golden color and look dry. Once baked, set aside to cool slightly.
While the quesitos are cooling, prepare the sugar glaze. In a small saucepan over medium heat, heat the sugar and water. Boil without stirring until the syrup has reduced and has the consistency of pancake syrup. Once the syrup has reduced, take off the heat and set aside.
When ready to serve, use a pastry brush and brush the tops and side of the quesitos with the sugar syrup. If also using the powdered sugar as an additional topping, the tops of the quesitos can be sprinkled with the powdered sugar.
Quesitos are best eaten when still warm. If there are leftovers, store in an air-tight container at room temperature for two days.