Step 1: In a large mixing bowl, using an electric mixer (stand mixer with paddle attachment or a hand mixer), beat the softened unsalted butter and softened full-fat cream cheese on medium-high speed until light, fluffy, and well combined. This should take about 3-5 minutes. Scrape down the sides of the bowl occasionally to ensure everything is incorporated.
Step 2: Gradually add the granulated sugar, about 1/2 cup at a time, beating well after each addition. Continue to beat on medium-high speed for another 5-7 minutes, until the mixture is very pale and fluffy. The sugar crystals should be mostly dissolved into the fat.
Step 3: Add the large eggs one at a time, beating well after each addition. Ensure each egg is fully incorporated before adding the next. If the mixture looks curdled, don’t worry, it will come back together with the flour.
Step 4: Stir in the vanilla extract, almond extract (if using), and lemon zest (if using).
Step 5: In a separate medium bowl, whisk together the cake flour, baking powder (if using), and salt.
Step 6: With the mixer on low speed, gradually add the dry ingredients to the wet ingredients, alternating with the whole milk. Begin and end with the dry ingredients. Mix only until no streaks of flour remain, being careful not to overmix.
Step 7: Pour the batter evenly into the prepared Bundt pan. Smooth the top with a spatula. Gently tap the pan on the counter a few times to release any large air bubbles.
Step 8: Place the Bundt pan into the preheated oven. Bake for 70-90 minutes, or until a wooden skewer or toothpick inserted into the center of the cake comes out clean. If the top is browning too quickly, loosely tent it with aluminum foil after about 45-50 minutes.
Step 9: Once baked, remove the cake from the oven and let it cool in the pan on a wire rack for exactly 15 minutes.
Step 10: After 15 minutes, carefully invert the cake onto the wire rack to cool completely. Allow it to cool for at least 1-2 hours before slicing.