In a medium bowl, add the cold cubed butter, flour, and confectioners sugar. Using your fingers, sift the flour mixtur over the butter and then start breaking down each cube into pea-sized pieces. When done, every ingredient should be well incorporated. (It is ok to have a few chunks.) Place in the refrigerator until ready to add the crumble.
In a large bowl, add the self-rising flour and yogurt. Use a spoon to mix together as well as you can, then switch to your clean hands. Mix with hands until ingredients are coming together and then turn out onto a clean surface to knead for about 5 minutes. If the dough is too dry (crumbly), add a tablespoon of yogurt. If it is too wet, add a tablespoon of self-rising flour. Once the dough is kneaded and smooth, roll it out into a 10-12 inch circle. It should be about 1/4 inch thick.
Place dough on a parchment-lined pizza stone or a parchment-lined baking sheet. Bake at 475°F for 8-10 minutes, or until the edges just start to brown. Remove from oven. (It will bake again once toppings are added.)
While the dough is baking for the first time, melt together butter, sugar, and cinnamon in microwave for about 30 seconds. Stir.
In a separate bowl, mix confectioners sugar and 1 tablespoon milk until smooth and creamy. If too thick, and in another tablespoon milk. Set aside.
Sprinkle the cold crumble topping over the cinnamon butter, getting out to the edges.
Place back into the oven for 6-8 minutes, or until the crumble no longer appears wet and is starting to turn golden brown.