Heat the oven to 350°F.
Grease a 9-inch cake pan with non-stick cooking spray and line the bottom with parchment paper.
Whisk the sugar, olive oil, and vanilla for 30 seconds.
Whisk in the eggs, and the yolk one at a time, and then the buttermilk, followed by the lemon juice.
Sprinkle the baking powder, baking soda, and salt into the bowl, one at a time, vigorously whisking after each.
Whisk in the flour until the batter is smooth.
Scrape the batter into the prepared pan and generously sprinkle the sugar over the top.
Bake for about 30 to 35 minutes, until a wooden skewer comes out with a moist crumb or two.
Let cool for about 20 minutes, then run a knife around the edges of the cake and invert the cake onto a serving platter.
Let cool to room temp.
