Preheat oven to 350° F Grease a 10” round cake pan and line the bottom with parchment. See the blog post for how to make a round cake pan liner.
Chop the fresh rosemary and zest then juice the oranges. Chop the fresh rosemary. Set all aside seperately.
Accurately measure the flour using the lighten, spoon, and swipe method. See the blog post for details. Use a large bowl to combine flour, sugar, baking powder, baking soda, chopped rosemary, and salt. Stir to evenly distribute and set aside.
2 ¼ cups all purpose flour, 1 cup granulated sugar, 2 teaspoons baking powder, ½ teaspoon baking soda, 1 Tablespoon fresh rosemary, ½ teaspoon salt
In a smaller bowl mix together the wet ingredients. Mix the orange juice and zest, oat milk, olive oil, and agave nectar.
7 Tablespoons freshly squeezed orange juice, 1½ Tablespoons orange zest, ¾ cup oat milk, ¾ cup olive oil, 2 Tablespoons agave nectar
Make a well in the middle of the dry ingredients and add the wet ingredients all at once. Stir until smooth but don't over mix. Scrape the batter into the prepared pan. Place the pan in the oven immediately as the orange juice and baking soda will begin reacting.
Bake for 40-45 minutes, until golden brown on the edges and the cake bounces back when lightly touched. Don't over bake or the cake will become dry.
Allow the cake to cool in the pan for at least 30 minutes before transferring to a cooling rack.
Make the icing. In a measuring cup or other small bowl combine the powdered sugar with orange juice until icing is at a pourable consistency.
¾ cup powdered sugar, 2 Tablespoons fresh orange juice
Pour the icing over the cake, tilting the cake to evening spread the icing around the top and start dripping down the sides. Optionally sprinkle some more orange zest on top.
more orange zest and/or rosemary for topping
Allow to cool and set completely before cutting into 8-10 slices.
Best the same day but can be stored covered in the fridge for up to 2 days. The icing will get sticky after being stored in the fridge.