A fancier chocolate cake
This is a more complicated chocolate cake, although considerably simplified from the New York Times recipe I started from. It has a lot of ingredients, but nothing complicated about putting them together, and it cooks pretty fast.
What about the frosting?
This really, really doesn't need frosting, especially if you eat it warm. We did have it with whipped cream and that was good but so rich.
How to make chocolate streusel cake:
First make the bottom and top streusel. In a medium-size mixing bowl, melt half a stick of butter and a quarter cup of semi-sweet chocolate chips in the microwave for one minute, or another minute if needed. Take it out and stir until all the chocolate is melted. Meanwhile, grease an 8x8 pan and line it with parchment paper. Add 1/4 cup of sugar and 1/2 cup of flour and mix. It will be a sort of thick paste. Add a quarter cup of chocolate chips and mix. Spread half of this paste in the bottom of the baking pan (doesn't have to be too even), and turn the other half out onto a clean board to wait for later.
Now make the batter for the main cake. In the same bowl, melt a stick of butter and the rest of the package of chocolate chips. Stir to melt and add 1/2 cup sugar, 1/2 cup brown sugar, 3/4 teaspoon baking powder, a pinch of salt, an egg, 2 teaspoons of vanilla, 1/2 cup thick yogurt and 1/2 cup of milk. Mix. Add 1 1/3 cups of flour and mix: you should get a pretty average batter; if it seems too thin add a little more flour. Pour that on top of the streusel and cover with the rest of the streusel that you set aside.
Bake at 350 for about half an hour or until not wobbly. Or bake for a shorter time if you want it molten in the middle. Lift the cake out of the pan by the edges of the parchment paper to cool. It will be rough and uneven on top, that's fine.
Vegetarian or vegan
Just naturally vegetarian! Enjoy! Or try this vegan chocolate mousse.
Can I keep this for later?
Sure. This chocolate cake will be fine for a week or so in the fridge.