Preheat oven to 350 degrees. Spray bundt pan with non-stick cooking spray.: As the oven warms you will notice a faint dry heat and the air in the kitchen shifting to a warm hum, which helps the batter spring into a steady bake. Preheating ensures even rise and predictable baking, so always wait until the oven reaches 350 degrees before you put the pan in. Greasing the bundt pan creates a smooth release and an even crust, so be thorough, getting into all the curves. A common mistake is putting the batter into an oven that is not fully preheated, which can cause uneven texture and collapse near the center. If you have a thermometer, verify the temperature for accuracy. Expect the oven to sing softly as it cycles, and watch for consistent heat before baking.
Beat first 3 ingredients in a mixer at medium speed until well-blended. Add eggs, one at a time, beating well after each addition. Beat in the lemon zest, lemon juice and vanilla.: You will smell the sugar and butter begin to soften and mingle, producing a faintly sweet, buttery aroma. Beating at medium speed incorporates air and gives the batter body, which affects crumb and texture. Adding the eggs one at a time encourages a smooth emulsion, preventing curdling and ensuring the batter is uniform. When the mixture is ready it should look creamy and slightly lighter in color. Stirring in the lemon zest , lemon juice, and vanilla releases bright citrus perfume that will carry through baking. A usual slip is adding eggs too quickly, causing the batter to break; if that happens, pause and scrape down the bowl and continue at a gentler pace to reemulsify.
In a small bowl, measure the 3 cups of flour. Remove 2 Tbsp and sprinkle over the blueberries, gently stirring and tossing to coat.: The sound of the flour sifting into a small bowl has a dry, floury scent. Reserving 2 tablespoons to coat the blueberries is a clever step to keep them suspended in the batter, rather than sinking to the bottom. As you toss the berries they should be lightly dusted and separated, not clumped. This slight coating helps the fruit integrate visually and texturally, so you get evenly distributed pockets of berry. A common mistake is over tossing which can bruise the berries, releasing juices that streak the batter; be gentle and use a light hand when coating.
Combine remaining flour, baking powder, baking soda, and salt. Add flour mixture to sugar mixture alternately with yogurt, beginning and ending with flour mixture.: When combining the dry ingredients you should notice a neutral, toasty scent from the flour . Alternating additions with the yogurt is about balance, it keeps the batter from becoming too stiff or too wet at any moment, so the crumb develops evenly. Start and finish with the dry mix for the best structure, folding gently to avoid overworking the batter. The batter should feel thick but pourable, and you will see it hold a ribbon briefly when lifted. Overmixing at this stage activates gluten and can make the cake tough, so stop mixing once streaks of flour are gone and the batter is cohesive.
Fold in blueberry mixture. Pour cake batter into a bundt pan. Bake at 350° for 1 hour or until a wooden pick inserted in center comes out clean.: Folding in the blueberry mixture requires gentle motions to keep berries intact, maintaining their juicy centers. The batter will become speckled with blue spots and smell faintly fruity. Pouring the batter into the prepared bundt pan, you should see a glossy, thick surface that fills the mold. As the cake bakes the kitchen will fill with warm, lemony aroma and you may hear the faint settling crackle as edges set. Bake for about 1 hour , checking toward the end by inserting a wooden pick into the center, which should come out clean or with a few moist crumbs. A common error is opening the oven repeatedly which causes heat loss and can make the center sink, so try to check sparingly and rely on the timer and visual cues.
Cool cake in pan 10 minutes; remove from pan. Let cake cool completely.: After you remove the cake from the oven, there is a wonderful waft of citrus and baked sugar. Cooling in the pan for about 10 minutes allows the structure to set so it unmolds cleanly; you will feel the cake slightly firm to the touch but still warm. When you invert the bundt pan, tap gently and let gravity help the loaf release. Let the loaf cool completely on a rack; this prevents the glaze from melting away when applied. A common mistake is glazing while the cake is too hot which leads to a runny, translucent coating, so patience here rewards you with a neat finish.
Combine powdered sugar and lemon juice in a small bowl; drizzle over warm cake. Cut with a serrated knife.: Mixing the powdered sugar with lemon juice yields a glossy, sweet tart glaze. Drizzling it over the warm cake allows the glaze to sink into the crumb slightly, creating both sheen and flavor contrast. The scent will sharpen to bright citrus, and the surface will take on a soft shine. Use a serrated knife to slice through the crust cleanly, as it will give neat portions without compressing the crumb. Avoid over saturating with glaze or the slices can become soggy, and be mindful that applying glaze to a piping hot cake will lead to excess runoff.
