This Blueberry Tart recipe is all about fresh berries and pure blueberry flavor. The tart shell is perfectly crumbly, sweetened appropriately as to not overwhelm the berries.
Pre-bake the tart shell according to this Tart Crust recipe. After you baked the tart shell according to that recipe, cool the tart crust completely. I often pre-bake the tart shell the day before I make the tart filling.
Make blueberry filling:
Mix corn starch with water in a small cup.
In a small pan, combine ¼ cup of water with 1 cup of berries, bring to boil, then cook on medium-low for about 10 minutes or longer until blueberries start breaking down and water becomes dark with color from blueberries.
Add corn starch mixture from step 1, lemon juice, lemon zest and sugar and continue cooking, mixing constantly, for 5-10 minutes on medium until blueberry mixture thickens and water is reduced.
Add 2 ½ cups of fresh berries, mix well. Remove from heat and using spoon, pour blueberry mixture evenly into cooled tart shell. Scatter ½ cup (or a little more) of fresh blueberries on top.