Heat 1/2 C sugar in heavy 8-inch skillet over medium heat, stirring constantly, until sugar is melted and golden brown.
Reduce heat to low.
Gradually add boiling water into sugar mixture; continue cooking until sugar is dissolved, stirring constantly. You need to stir really quickly here to keep the sugar from glomming up.
Beat egg whites in medium bowl at medium speed with electric mixer until soft peaks form.
Gradually add 1/2 C granulated sugar, beating at high speed until stiff peaks form; set aside.
Combine flour, baking powder and salt in medium bowl; set aside.
Beat butter and remaining 1/2 C sugar in large bowl until light and fluffy.
Beat in egg yolks and vanilla extract.
Gradually add sugar syrup, mixing until well blended.
Add dry ingredients to butter mixture alternately with milk, beating well after each addition.
Fold in egg white mixture.
Fill cupcake liners halfway full*
Bake at 375 F for 20 minutes.
Jam Glaze Instructions
Heat jam in a small saucepan on medium-high heat until it resembles a thick syrup.
Add in water and stir.
Remove from heat and strain out bits of fruit and seeds.
Let cool.
Mix in powdered sugar.
Spread on cupcakes.
Notes
*The Jam FilllingLike the hamantashen cookies, the hamantashen cupcakes need a jam filling. You can use the same filling that you used in your hamantashen cookies or mix and match flavors. The easiest way to fill the cupcakes is to load the filling into a piping bag, shove the bag into the cupcake while it is still slightly warm, and squeeze. If you don't have a piping bag, you can always use a small paring knife to cut a hole in the cupcake, spoon in some filling, and then replace the cake that you removed.**The jam glaze served as the glue to keep the hamantashen cookie stuck on the hamantashen cupcake. It also added a nice, sweet moist layer to top off each cupcake bite. I would suggest making the jam glaze with the same jam that you used as a filling, but again, you can always mix and match flavors.