Prepare the streusel: Put the flour and sugar into a medium bowl and add the butter cut into pieces. Combine with your fingers and create powdery crumbles.
Grease the baking dish with a piece of butter and dust with flour.
Combine the dry ingredients: flour and baking soda.
Crack the eggs into a large bowl. Whip them with an electric hand mixer on high speed, and slowly add the granulated sugar (not all at once, as you’d choke up the batter). Continue whipping this mixture until you’ve put in all the sugar; the egg mixture will slowly get bigger, thicker, and lighter. It takes about 5 minutes until the eggs turn foamy.
Little by little, add the oil, buttermilk, and flour mixture.
Mix shortly everything with an electric mixer set to low speed until combined.
Pour the batter into a prepared pan. Put the apricot halves (or roughly chopped apricots) on top of the cake, and sprinkle with a thick layer of crumb topping.
Put the apricot cake into the preheated oven on the middle wire rack and let it bake for around 30-40 minutes. Once its surface turns golden brown, you’re done.
Notes
Makes about 12 portions.
I used a 13-inch (34 cm) round baking pan.
SERVING: Let the apricot coffee cake cool, cut it into pieces, and serve it for breakfast or brunch with a cup of coffee or tea.
If there is anything left over, cover them with plastic wrap and store it in the fridge. Here this moist cake will keep for up to five days.