Preheat oven to 350 degrees F. Line 9x13 pan with parchment. Set aside.
With a mixer, beat butter with sugar until light and fluffy, about 3-4 minutes. You will likely have to use a spatula to scrap down the sides of the bowl at least once.
Add eggs, beating in each time. Add vanilla with the last egg.
Add flour, baking powder and baking soda. Mix to just combine. Don't over mix.
Add ricotta and milk. Combine. I used the spatula to ensure the bottom was evenly mixed in.
Pour into pan and spread evenly. The mixture was rather thick. Bake for approx 30-40 minutes. You will know when it is done when a toothpick inserted in the middle comes out clean and the edges are lightly golden.
While the cake is baking, make the glaze. Combine lemon juice and sugar in bowl. Use the back of the spoon to press out any large lumps of sugar. Alternately, you could press the sugar through a fine sieve before adding to the lemon juice to prevent lumps.
When the cake comes out of the oven, poke evenly with the toothpick all over, and drizzle evenly with the lemon glaze. Do this while the cake is hot. Let rest in the pan until moderately cool, then lift out using the parchment paper. Serve as is or ice with a white/lemon icing.
I did not test this but I suggest that you could make this more lemony if you finely grate the peel of the 1/2 lemon and add this into the cake mixture. I'd add it with the ricotta and milk near the end.