Wacky Buttermilk Cake

Preheat oven to 350°F (175°C). Grease and flour a 9-inch round cake pan.

Combine flour, sugar, salt, cocoa, and cinnamon in a large mixing bowl, whisking together to distribute dry ingredients evenly.

Heat butter and water together in a small saucepan over medium heat until butter melts and mixture is combined, about 2-3 minutes.

Pour the hot butter-water mixture into the dry ingredients and stir until just combined; do not overmix.

In a small bowl, whisk together eggs, buttermilk, vinegar, and vanilla until well blended.

Add the wet mixture to the dry ingredients and stir gently until no flour streaks remain; the batter will be thin.

Sprinkle baking soda over the batter and fold in gently until just combined; do not overmix as the batter will bubble slightly.

Pour batter into prepared pan and smooth the top. If using, scatter chocolate chips evenly over the surface.

Bake for 30-35 minutes, or until a toothpick inserted in the center comes out clean or with a few moist crumbs.

Remove from oven and allow cake to cool in pan for 10 minutes before turning out onto a wire rack to cool completely.