Butter and lightly flour a 9’x13’ cake pan. Preheat oven to 350 degrees.
In a stand mixer, with a paddle attachment, beat butter until smooth and fluffy- about 2 minutes. Stir in sugar and beat the mixture on medium high speed for about two minutes until the sugar crystals have fully dissolved into the butter. Scrape down the sides of the bowl. Beat in the eggs, one at a time until fully incorporated. On low speed add in the milk and ricotta and vanilla paste. Scrape down the sides of the bowl.
Mix the flour, baking powder and baking soda and salt in a bowl. With the mixer on low, add in the flour mixture to the bowl, one cup at a time. Mix on low until he flour mixture is fully incorporated into the batter. Using a silicone scraper, spread batter into the prepared cake pan and level with an off-set spatula. Bake at 350 for about 20-25 minutes. Remove the cake from the oven and set on a wire rack to cool. Let cool for 10 minutes, loosen the edges of the cake with a knife then turn out of the pan.