Rasberry Buttermilk Cake

Adapted from Gourmet, June 2009
You can just ignore the word “raspberry” up there and swap it up with any which berry you please, like blackberries or blueberries or bits of strawberries or all of the above. This is a good, basic go-to buttermilk cake (not unlike a lemon yogurt cake before it) — moist and ever-so-light — a great jumping off point for whatever you can dream up.
By the way, I was having a “moment” when I made this and for once, remembered to weigh my ingredients as I measured them, for all of you people out there that know weighing is way easier than dirtying a zillion cups and spoons. Now let’s just hope my scale is accurate.
Makes one thin 9-inch cake, which might serve eight people, if you can pry it from first two people’s grasp
1 cup (130 grams) all-purpose flour1/2 teaspoon (2 grams) baking powder1/2 teaspoon (2 grams) baking soda1/4 teaspoon salt1/2 stick (56 grams) unsalted butter, softened2/3 cup (146 grams) plus 1 1/2 tablespoons (22 grams) sugar, divided1/2 teaspoon pure vanilla extract1/2 teaspoon finely grated lemon zest (optional)1 large (57 grams) egg1/2 cup well-shaken buttermilk1 cup fresh raspberries (about 5 oz)
Preheat oven to 400°F with rack in middle. Butter and flour a 9-inch round cake pan.
Whisk together flour, baking powder, baking soda, and salt and set aside. In a larger bowl, beat butter and 2/3 cup (146 grams) sugar with an electric mixer at medium-high speed until pale and fluffy, about two minutes, then beat in vanilla and zest, if using. Add egg and beat well.
At low speed, mix in flour mixture in three batches, alternating with buttermilk, beginning and ending with flour, and mixing until just combined.Spoon batter into cake pan, smoothing top. Scatter (see Note) raspberries evenly over top and sprinkle with remaining 1 1/2 tablespoons (22 grams) sugar.
Bake until cake is golden and a wooden pick inserted into center comes out clean, 20 to 25 minutes. Cool in pan 10 minutes, then turn out onto a rack and cool to warm, 10 to 15 minutes more. Invert onto a plate.
[Baking time updated, shortened, after so many of you concurred that this cake bakes crazy quickly.]
Note: Directions like “scatter” always scare me. Where’s the science? Here’s what my neuroses taught us: the ones that were downward were almost all swallowed by the batter. The "o" ones stayed empty, like cups. Both were delicious.
Make your own buttermilk: No need to buy buttermilk especially for this or any recipe. Add one teaspoon tablespoon [updated, as an astute reader pointed out that the larger amount is more common] of vinegar or lemon juice to one cup of milk and let it sit until it clabbers, about 10 minutes. Voila, buttermilk!