Sprinkle the gelatin over the water in a small bowl and let sit for about 5 minutes.

In a small saucepan over low heat, combine the milk, sugar, and vanilla extract and let simmer, stirring occasionally, until the sugar dissolves. Remove from the heat and stir in the gelatin water until it dissolves. Add the lemon zest and lemon extract. Whisk the mixture into the Greek yogurt and divide into serving dishes.

Chill for 3 to 4 hours. Serve with fresh berries on top.