Step 1

Mash 1 banana in a medium bowl. Add yogurt and sugar and mix well.

Step 2

Sprinkle about 2 tablespoons crushed cookies in the bottom of 4 clear 8-ounce glasses. Slice the remaining 2 bananas. Top the cookie layer with about 3 tablespoons yogurt mixture and 3 or 4 banana slices. Repeat the layers 2 more times. Top with any remaining crushed cookies and whipped cream, if desired.