Fill a cocktail shaker with ice. Add the pineapple juice, lime juice, whipped cream vodka, RumChata, and green food coloring Secure the lid tightly and shake vigorously until the shaker is cold, about 30 seconds.
Spread some graham crackers crumbs out on a small plate. Run a lime wedge around the rim of a martini glass and dip the rim into the graham cracker crumbs.
Pour the cocktail into the prepared glass. Top with a dollop of whipped cream and sprinkle with additional graham cracker crumbs, if desired. Garnish with a lime wheel and serve immediately.
Notes
You can skip the food coloring if you prefer, but the cocktail will look white and not green in any way.