Adorable filled cupcakes might seem like a project best left to the professionals, but let me reassure you that they're not; the requisite technique is actually quite easy to master (with a little guidance, of course). Follow along with this step-by-step guide and you'll be piping eye-catching filling into your favorite petite treats in next to no time.
Remove the Centers
Insert the base of a large pastry tip (I use Ateco's #800 
) into the center of the cupcake about 1/4-inch deep (1/2-inch deep if filling and then frosting), and twist until the cake center twists alongside the tip; pull directly up to remove the center. Reserve the cake centers if your cupcakes will be frosted (rather than just filled), otherwise discard or eat the centers.
Dust With Powdered Sugar
If dusting the cupcakes with powdered sugar, do it now, as otherwise you'll coat the filling with powdered sugar. Spoon about a tablespoon of powdered sugar into a fine mesh strainer and sift it over the cupcake tops.
Fill the Pastry Bag
Nestle a disposable pastry bag 
(or large resealable bag) in a pint glass, folding the top half over the glass rim (this helps keep things tidy). Spoon in the filling until it reaches the glass's brim; firmly tap the glass on the counter to settle the pastry bag's contents.
Pipe In the Filling
Securely twist the pastry bag until it's taut; snip off the tip of the bag and deposit the filling in the wells of the cupcakes by twisting the top of the bag to apply pressure and pipe out the filling.
If frosting the cupcakes after filling, leave about 1/4-inch headroom in each cupcake. Slice off all but the top 1/4 inch of the reserved cupcake centers to make a thinner disc, and then nestle them on top of the filled centers, pressing them in until they're roughly flush with the cupcake tops. Proceed with piping frosting.
Dig in to your cupcakes right away; the filling will begin to leach into the cake, so pipe them at most three to four hours before consuming.
Practice this technique with: Irish car bomb cupcakes