Best Strawberry Cake Recipe

• Prep: Preheat the oven to 350°F. Line a 9×13 pan with parchment paper, allowing 2 to 3 inches to extend over the long sides. Spray lightly with cooking spray with flour.
• Create powder: Add the freeze-dried strawberries to a food processor and process into a fine powder; transfer to a large mixing bowl.
• Puree Strawberries: Add 8 ounces to the food processor (no need to wipe it out first). Run the processor until they’re mostly pureed, leaving a few small strawberry chunks. See pictures in the post. You should have roughly ¾ cup-a little less is okay, but don’t use more. Set aside. 
• Combine Dry Ingredients: Reserve 2 teaspoons gelatin for the frosting. Add the rest to the large mixing bowl with the freeze-dried strawberry powder. Add the cake flour (measure correctly! See Notes), baking powder, baking soda, and salt. Whisk together and set aside.
• Cream Butter and Sugar: Using a stand mixer fitted with the paddle attachment (or a handheld mixer), beat the butter and sugar on medium-high speed for 3-5 minutes (no less!), until very creamy and fluffy, occasionally scraping down the bowl.
• Add Wet Ingredients: Scrape down the bowl. Add the sour cream, oil, and vanilla extract, and beat on medium-high until combined, about 30 seconds. Mix in the eggs and the egg yolks, one at a time, blending each fully into the batter before adding the next to prevent an “eggy” taste.
• Alternate Ingredients: With the mixer on low, add the flour mixture in three additions, alternating with the milk (begin and end with dry ingredients). Stop mixing when a few steaks of flour remain. Fold in the strawberry puree, but don’t overmix. Pour the batter evenly into the prepared pan and smooth into an even layer.
• Bake at 350° for 35 to 45 minutes or until a wooden pick inserted in the center comes out clean. Cool completely before frosting.

FROSTING

• Note: This is a unique method from Cook's Illustrated that makes the frosting thicker and more stable. It will look super thick at first, but it will thin to the ideal consistency when you add the cream cheese.
• Using a stand mixer fitted with a paddle attachment (or a hand mixer), beat the butter and sugar on low speed, then gradually increase to medium-high to prevent powdered sugar from flying everywhere. Continue to beat on medium-high for 3 minutes. It will be powdery, but should come together by the end. (If not, no worries, proceed to the next step.)
• Add the cream cheese 1 piece at a time, beating a few times after each addition. Scrape down the bowl as needed.
• Beat in the lemon juice, vanilla, and salt, then add the 2 teaspoons gelatin. If it’s too sweet, beat in a pinch of salt. If it’s too runny, beat in a little more sugar, then adjust with salt as needed or pop it in the fridge for 15 minutes.
• Spread the frosting evenly over the cake and garnish with fresh strawberries.