Preheat the oven to 375 degrees . In a medium bowl, toss the strawberries with 1/4 cup of the sugar. In another bowl, mix the ricotta with 1 1/2 tablespoons of the sugar.
In a mixer with a paddle attachment, combine the butter, the remaining 1/4 cup of the sugar, the lemon zest and a pinch of salt. Add the flour, about 1/4 cup at a time, mixing as you go, until a dough forms. (It will be crumbly but should stick together.)
Transfer the dough to a parchment-lined 9-inch square baking pan and press it into an even layer. Sprinkle with coarse sugar and prick all over with a fork, making sure to poke all the way through. With the handle of the fork, score the dough into 8 equal rectangles.
Bake the shortbread until the edges are browned and the middle is golden, 20 to 25 minutes. Let the shortbread cool in the pan for about 5 minutes (it will darken slightly), then cut along the scored lines while the shortbread is still warm. Transfer the pieces to a cooling rack and let cool completely.
Divide the ricotta equally among 8 shallow bowls, then top with the strawberries and their juices and a piece of shortbread.