Pre- heat oven to 350F (175C) and grease and flour a 9" (23 cm) cake pan.
In a large bowl whisk together the flour, sugar, salt and baking powder. Add the cubed cold butter and mix until the mixture becomes coarse crumbs.
Remove ¾ cup of the crumbly mixture and place in a small bowl, stir in the cinnamon, this will be your streusel topping, set aside.
In a small bowl toss together the chocolate chip and 2 teaspoons of flour, set aside.
In a medium bowl add the milk, eggs, and vanilla, beat with a fork until combined. Add the wet mixture to the flour mixture. Stir with a wooden spoon or spatula just until moistened, stir for 15-16 stirs (no more). Gently fold in the chocolate chips.
Spoon the batter into the prepared cake pan and sprinkle with the topping. Bake for approximately 45-55 minutes check for doneness with a toothpick. Let cool in pan 15-20 minutes then move to a wire rack to cool completely or let cool completely in the pan, before serving. Enjoy.
Notes
To make homemade cake/pastry flour - For every cup of all purpose flour, remove two tablespoons and replace with two tablespoons of corn starch. Be sure to sift the flour and cornstarch together a couple of times, this way it is sure to be properly combined and lump free. Cake flour in cakes will give you a very tender texture and fine crumb, it will also help the cake to rise.Tip - Place butter in the freezer and then grate directly into the dry ingredients, mix with a fork until you have coarse crumbs.If you prefer you can substitute vanilla bean paste for extract at a one for one substitution. Or you could use a vanilla bean, half a bean for one teaspoon of vanilla extract.To store the cake - be sure to wrap the cake in plastic wrap or foil to prevent the cake from drying out. It will last up to two days at room temperature. It can also be stored in the fridge tightly wrapped to prevent it from drying out and will keep for up to 5-7 days.To freeze the cake - be sure to wrap it tightly with plastic wrap and place in a freezer safe container or bag. It will keep for up to three months in the freezer. Thaw the cake in the fridge, then bring it to room temperature before serving. You could also cut individual pieces, wrap them separately and freeze. And remove pieces when needed.