In a small saucepan, combine blueberries, honey, and lemon juice over medium heat and simmer for 5 minutes until blueberries soften.
If using, dissolve cornstarch in water and stir into blueberry mixture to thicken. Remove from heat and cool completely.
Mix Greek yogurt and vanilla extract in a bowl until smooth. Adjust sweetness with more honey or maple syrup if desired.
Spoon yogurt into silicone molds or mini muffin tins, filling about three-quarters full.
Add a spoonful of cooled blueberry compote on top of each yogurt portion and swirl gently with a toothpick to create a marbled effect.
Freeze molds for at least 3 hours until solid.
Remove frozen bites from molds and store in an airtight container in the freezer. Let sit 2–3 minutes before eating for best texture.
