Position rack in hottest area of oven. Preheat oven to 375°F/190°C. Coat the inside of a 10-inch (25 cm) loose bottom tart pan with nonstick spray.

Roll the All Butter Pie Crust out on a lightly floured surface or between two pieces of parchment paper to about 1/8 to 1/4-inch in thickness (3mm to 6 mm). Transfer to prepared pan and press all along the bottom and sides. Trim flush with top edge. Freeze for 15 minutes while oven preheats. Line tart with foil and pie weights and bake for 15 minutes or until pastry is set and beginning to color, then remove foil and weights and bake for about 10 minutes for or until it is an even light golden brown all over. Cool completely on rack.

For the Filling: Separate out 8-ounces (225 g) of the berries, roughly chop them and set aside. Whisk the sugar and cornstarch in a medium sized saucepan, then whisk in water and lemon juice until combined. Scrape in all of the chopped berries and any juice. Bring to a boil over medium heat, mashing with a potato masher occasionally, then adjust heat and simmer vigorously for a minute or two until thick and glossy, whisking as needed. Press through a wire meshed strainer, pressing solids with a silicone spatula to extract as much fluid glaze as possible. Discard any solids and cool glaze until barely warm.

Meanwhile, leave the smaller berries whole and halve any very large ones. Place these berries in a large mixing bowl, then scrape glaze over and use a large silicone spatula to fold together well, making sure that all the berries get a nice glossy coating of glaze.

Scrape berries out into cooled tart shell and spread evenly, gently mounding in center. Refrigerate until set, about 1 hour. Tart is best eaten the day it is made. Serve slightly chilled or at room temperature. We garnished with edible flowers; you can also offer the optional lightly sweetened whipped cream, if desired heeding a maximum of 1/2 cup (125 ml) whipped cream per serving.