Blueberry Buttermilk Breakfast Cake

I swear buttermilk is magic. It seems to turn everything into gold: super-moist, super-delicious gold.
This morning I awoke needing a simple, summery, cake-like-but-not-dessert-like breakfast treat. One of Ben’s friends had crashed here last night, and I thought it only appropriate to treat him to a proper breakfast. In other words, I was craving sugar and carbs. The truth is I’ve been craving sugar and carbs and a cake like this for months. But seriously, who doesn’t need a good, seasonal, berry cake recipe in their morning-treat repertoire?
Nobody. And I think I’ve found the recipe that fits the bill. On an old photocopied sheet of paper in my mother’s hand writing, I spotted a note: “Baby Boy’s Favorite.” Oh Baby Boy. Baby Boy is my younger brother, my parents’ favorite child, and one of the most satisfying people to cook for. If it was Baby Boy’s favorite cake, it would soon be mine, too. This cake is delectable! I think you’ll like it, too.

Ingredients
½ cup unsalted butter, room temperature
2 tsp. lemon zest or more — zest from 1 large lemon
⅞ cup* + 1 tablespoon sugar for sprinkling
1 egg, room temperature
1 tsp. vanilla
2 cups flour (set aside ¼ cup of this to toss with the blueberries)
2 tsp. baking powder
1 tsp. kosher salt
2 cups fresh blueberries
½ cup buttermilk**
* ⅞ cup = ¾ cup + 2 tablespoons

** To make homemade buttermilk, place 1 tablespoon of vinegar or lemon juice in a liquid measuring cup. Fill cup with milk until it reaches the 1-cup line. Let stand for five minutes. Use only ½ cup of the prepared mixture for the recipe.

Steps
Preheat the oven to 350ºF. Cream butter with lemon zest and ⅞ cup of the sugar until light and fluffy.
Add the egg and vanilla and beat until combined. Meanwhile, toss the blueberries with ¼ cup of flour, then whisk together the remaining flour, baking powder and salt.
Add the flour mixture to the batter a little at a time, alternating with the buttermilk. Fold in the blueberries.
Grease a 9-inch square baking pan (or something similar) with butter or coat with non-stick spray. Spread batter into pan. Sprinkle batter with remaining tablespoon of sugar. Bake for 35 to 45 minutes. Check with a toothpick for doneness. If necessary, return pan to oven for a couple of more minutes. (Note: Baking for as long as 10 minutes more might be necessary.) Let cool at least 15 minutes before serving.
Enjoy!!