Brew/prepare coffee according to the package directions. Set aside 2 Tbsp, then pour the rest into a bowl.
In a separate medium bowl, combine maple syrup, vanilla, and softened mascarpone with a spoon until smooth. (You may need to mash the mascarpone until it softens enough). Add Greek yogurt and mix until fully combined. Spoon or pipe about 1/4 cup of the mixture into each parfait glass.
Break 2 Biscoff cookies into 3 pieces each. Quickly dip them in the bowl of coffee until just submerged, then layer them over the mascarpone/yogurt mixture in each glass. Continue with each glass.
In a microwave-safe bowl or mug, microwave the 2 Tbsp of brewed coffee that you set aside previously, until hot. Stir in the Biscoff cookie butter spread. Drizzle about 1-2 tsp of this mixture over the first layer of Biscoff cookies. Top this with another 2 Biscoff cookies broken and dipped in coffee.
Continue layering in this manner: add another layer of the mascarpone/yogurt mixture, then another layer of Biscoff cookies, cookie butter/coffee mixture, and more Biscoff cookies. Top each glass with a layer of whipped cream if desired.
In a small bowl, combine cocoa powder and espresso powder. Use a sifter to dust the mixture over the tops of the glasses.
Cover the parfait glasses with plastic wrap. Chill for at least an hour in the refrigerator, then serve!