Campari Olive Oil Cake

I would never have picked this cake out of Melisa Clark's most recent cookbook, Dinner in France, if a fellow member of our cookbook club hadn't pointed it out.  My spouse found a grapefruit and an orange in the fridge and made it.  So goo, with a real grown up flavor, and a moist crumb that I love.

• ¼ cup/55 grams unsalted butter (1/2 stick), melted, plus more for greasing the pan
• 2 cups/255 grams all-purpose flour
• 1 ⅔ cups/330 grams granulated sugar
• 1 teaspoon fine sea salt
• 1 teaspoon baking powder
• ½ teaspoon baking soda
• ⅔ cup/160 milliliters whole milk
• ⅔ cup/160 milliliters mild olive oil
• 3 large eggs
• ⅓ cup/80 milliliters Campari
• 1 tablespoon grated grapefruit zest
• 1 tablespoon grated orange zest
• 1 teaspoon grated lemon zest
• ¼ cup/60 milliliters fresh grapefruit juice
• 2 tablespoons fresh orange juice
• 1 tablespoon fresh lemon juice
• Whipped cream, sweetened or not as you like, for serving

1. Heat oven to 350 degrees. Grease a 9-inch springform pan, and line the bottom with parchment paper. (You can use a regular 9-inch cake pan that is at least 2 inches deep, but the cake will be harder to unmold.)
2. In a medium bowl, whisk together flour, sugar, salt, baking powder and baking soda. In a large bowl, whisk together butter, milk, oil, eggs, Campari, citrus zests, and citrus juices. Fold in the dry ingredients, then scrape the batter into the prepared pan.
3. Bake until the top is golden and springs back when lightly pressed in the center, 45 minutes to 1 hour. (A cake tester might emerge with a few crumbs, which is OK.)
4. Let the cake cool completely in the pan. Then run a butter knife around the edges and release the sides. Serve with dollops of whipped cream.