In a 5 to 6 quart crockpot wisk together the condensed milk and whole milk, stir in rice.
Cook covered, until the rice is tender and the mixture has slightly thickened, about 2 to 3 hours on HIGH. Remove from heat and stir in vanilla.
Drizzle the hazelnut-chocolate spread over the rice pudding and gently fold in to create swirls; spoon into bowls and top with strawberries if desired.