Prepare a rectangle fluted flan pie pan (about 35 x 12cm) or a 9 inch round pie tray. Line base with parchment paper. Preheat oven to 190 deg C.
Combine sugar and cinnamon in a small bowl, set aside.
Peel, core and slice the apples, not too thin, into the bowl. Add the cinnamon sugar mixture and ½ tbsp lemon juice and toss to thoroughly with the apple slices, set aside.
Sieve flour and baking together into a bowl, set aside. Cream butter, lemon zest and sugar till light and fluffy. Slowly add in beaten egg, lemon juice and vanilla extract. Lastly add the flour mixture and fold well with a rubber spatula until combined.
Spread batter evenly in the prepared pan.
Arrange the apple slices on top of the batter in rows (drain excess water from the apples) and sprinkle some coarse sugar or raw sugar on top. You may also add some raisins over it if you like.
Bake for about 30 minutes or a cake tester in the center comes out clean and cool the cake tart in the pan.
Recipe by Anncoo Journal at https://www.anncoojournal.com/apple-cake-tart/