Prepare the Hibiscus Syrup: Combine water, sugar, and dried hibiscus flowers in a small saucepan. Bring to a gentle boil, then reduce heat and simmer for 5 minutes until the liquid is deeply colored.

Strain the Syrup: Remove the saucepan from the heat, let the mixture steep for another 5 minutes, then strain out the hibiscus flowers completely. Allow the syrup to cool slightly.

Muddle the Raspberries: Divide the fresh raspberries between two mugs. Lightly mash (muddle) them at the bottom of each mug to release their juices.

Assemble the Base: Add 2 tablespoons of the prepared hibiscus syrup and the vanilla extract to each mug over the muddled raspberries. If using espresso, pour the shots into the mugs now.

Steam the Milk: Steam or froth the milk until hot and airy. Pour the steamed milk carefully over the syrup mixture in each mug, using a spoon to hold back the foam initially if desired.

Finish and Serve: Top each latte with the accumulated milk foam. Garnish with a few fresh raspberries or a sprinkle of dried hibiscus dust, if available.