Combine flour, sugar and salt in a bowl. Add the butter and rub it into the flour with your fingers until the mixture is coarse crumbs. Add 3 tbsp water and mix with a fork. Use hands to knead the dough in the bowl until it forms a ball. Flatten ball into 1-inch thick square, then wrap it in plastic and chill for an hour.
Combine ground almonds, mascarpone, 2 tbsp honey and vanilla in a bowl and mix until smooth. Reserve.
In another bowl, combine the strawberries, sugar and flour and reserve.
Preheat oven to 400 degrees.
Remove dough from fridge and let it sit on the counter for a few minutes. Roll it out on a floured work surface to a 14-inch square, then transfer to a parchment-lined baking sheet.
Cover the dough with the mascarpone filling leaving a border around the edges.
Arrange the strawberries over the filling.
Fold edges of dough over the strawberries and pleat or crimp the edges.
Combine egg yolk and milk and brush over the crust.
Bake until golden-brown, about 40 minutes.
Heat reserved honey and brush it over the strawberries.