In a small saucepan, over medium heat, add blueberries, sugar and lemon juice. Stirring constantly, cook until blueberries burst and the syrup thickens, about 5-7 minutes. Remove from heat and refrigerate in an air-tight container until ready to use.
Chill the mixing bowl (metal or glass) and your whisk attachment for 5-10 minutes.
Pour cold whipping cream and a ½ teaspoon of vanilla extract into the chilled bowl. Using the whisk attachment, whip on high speed until the mixture begins to thicken and soft peaks form. Turn speed to low and slowly add the sweetened condensed milk. Increase the speed to medium and continue mixing until stiff peaks form.
Place half of the vanilla cream into a chilled, 2-quart loaf pan, spoon half of the blueberry compote on top. With a spoon or knife, gently swirl the blueberry compote into the vanilla cream.
Repeat by layering with the other half of the vanilla cream and blueberry.
Loosely cover and freeze for at least 6 hours, preferably overnight, before serving.