1 small chocolate-covered honeycomb bar or extra digestives, crushed, to decorate
Spoon the strawberry jam into the bottoms of 4 tall glasses. Stir the brown sugar into the Greek yogurt and divide half the mixture between the glasses.
Place the digestive biscuits in a freezer bag and crush with a rolling pin, then use the crumbs to cover the yogurt. Spoon over the remaining yogurt and serve sprinkled with shards of chocolate-covered honeycomb or extra crushed digestives.