Lemon Olive Oil Cake

1 Heat oven to 350 F / 177 C degrees.
2 Place butter in the center of a 9-inch cake pan (an 8-inch pan will work too) and set the pan in the oven. Leave the pan in the oven for a few minutes, and remove it as soon as the butter melts. Swirl the pan so that the butter coats the bottom of the pan.
3 Sprinkle light brown sugar over the top of the melted butter, breaking up any large pieces with your fingers. Place lemon slices in a single layer over brown sugar. (Be a little artistic here - this will be the top of the cake!)
4 In a large mixing bowl, combine lemon zest and sugar and rub with your fingers until it looks like wet sand. Whisk in buttermilk, lemon juice, and eggs until evenly combined.
5 In a second bowl, combine flour, poppy seeds, baking powder, baking soda, and salt.
6 Add dry ingredients to wet ingredients in three increments, stirring between each addition. Add oil and whisk to combine.
7 Pour batter over lemon slices in prepared pan.
8 Bake until center is set, 45 to 50 minutes. Let cake cool at room temperature before inverting the pan over a plate or cutting board. Slice and serve!
9 Cake will stay moist if stored in the fridge, covered, for 2 to 3 days.