I made those tarts a few weeks ago when it was still summery in New York. Although berries are in season during summer time, you can always get frozen berries at anytime of the year and make some berry tarts.
2 C fresh or frozen berries
2 Tbsp granulated sugar
zest of one lemon
1 Tbsp all-purpose flour
1. Press chilled tart dough into tart pan, chill for another 20 minutes while you make the berry filling.
2. In a saucepan over medium heat, cook berries, sugar, lemon zest, and flour until mixture starts to boil.
Turn heat down to low and let it simmer until the berries are soft enough to mash with a fork and the sauce is thick enough to coat the back of the spoon. Remove from heat and then preheat the oven to 375F
3. When the berry filling has cooled to room temperature, drop in about two tablespoons of it for each tart
4. Bake for 20-25 minutes or until the crusts begin to brown
* A lot of time when people make jam they tend to add tons of sugar to the fruit; but I think it’s unnecessary because most of the fruits are already sweet to begin with, especially berries. I’ve even tried not adding sugar at all, and the “jam” I made turned out amazing. So feel free to omit the sugar or substitute it with honey if you like.