Verdict: Nailed it!
Super easy and it thrilled my 5 year old!
Here's what you do:
First: Invest in a few basic mini cookie cutters. (I've used mine more times than I can count: Jello Jigglers, cutting bologna and cheese into fun shapes for lunches, shaped quesadillas, cutting fresh fruit....)
Cut out a shape in the lower corner of ONE slice of bread.
Add peanut butter (and/or jelly) to the second slice:
Put the bread together.
Gently shake the sprinkles into the cut out shape.
Tip: if too much pours out (as it did for me) just shake off the extras into the sink. The base layer will stick to the peanut butter.