Preheat the oven to 350°F or 180°C. Brush your tart pan with oil, then dust it with flour.We recommend using a tart pan with removable bottom.
Add the sugar, water, oil, and orangezest to a large mixing bowl and mix well with a spatula.
In a separate bowl, mix flour and baking powder.Add them to the bowl with the wet ingredients all at once.Mix wet and dry ingredients until the liquids absorb the flour without overmixing.
Compact the dough with your hands for a few seconds until it comes together.You don't have to knead the dough but only compact it together.
Take about ¾ of the dough and transfer it to the tart pan. Flatten it with your hands to cover the bottom and sides.Prick the bottom and sides with a fork.
MAKE RICOTTA FILLING
To a bowl, add the ricotta, orange zest, mini dark chocolate chips, sugar, and vanilla extract.
Whisk until well combined.
Pour the ricotta mixture into the crust and flatten it with the back of a spoon.
MAKE LATTICE TOP
On a worktop dusted with flour, roll out the leftover dough thinly, and cut out nine stripes with a sharp knife or pastry wheel cutter.
Arrange the stripes on top of the tart, 5 in one direction and the other 4 in the opposite direction.Push down the edges with your fingers or with a fork to attach the stripes to the edge.
Bake in the oven at 350°F or 180°C for about 45 minutes.
Let cool down completely (we recommend 3 hours if you want a perfect slice like in the pictures) before taking it out of the tart pan and transferring it onto a pie plate.You can dust the top with powdered sugar to make it look prettier, then slice it and enjoy.