Prep: Heat oven to 350°F (175°C). Grease and line two 8-inch round cake pans with parchment.
Mix dry: In a bowl, whisk 2 1/2 cups flour, 1 1/2 tsp baking powder, 1/2 tsp baking soda, and 1/2 tsp salt.
Citrus base: In a large bowl, combine 1 cup sugar with the zest of 2 oranges.
Rub with fingers to release oils.
Cream: Add 1/2 cup softened butter to the sugar-zest mixture. Beat until light and fluffy, 2–3 minutes.
Wet ingredients: Beat in 1/4 cup neutral oil, then 3 eggs, one at a time. Stir in 1 tsp vanilla and 1–2 tsp orange extract (optional).
Liquid: Combine 3/4 cup milk with 1/3 cup fresh orange juice.
Combine: Add dry ingredients to the butter mixture in two parts, alternating with the milk-orange mix.
Mix just until smooth.
Bake: Divide batter between pans. Bake 23–28 minutes, until a toothpick comes out clean. Cool 10 minutes, then turn out onto racks to cool fully.
Orange syrup (optional but great): Simmer 1/4 cup orange juice with 2 tbsp sugar until slightly thick, 3–4 minutes.
Brush over cooled cake layers.
Frosting: Beat 8 oz softened cream cheese and 6 tbsp softened butter until smooth. Add 2 1/2–3 cups powdered sugar, 1 tsp vanilla, and a pinch of salt. Beat until creamy.
Slowly stream in 1/3 cup cold heavy cream and whip until fluffy. Fold in 1 tsp orange zest for extra citrus.
Assemble: Place first layer on a stand. Spread frosting, add second layer, and frost top and sides.
Swirl for a soft, rustic finish. Garnish with extra zest or thin orange slices.