Why did my apple crumble explode?

Chef's answer
If crumble is sinking into apple you need more crumble. Maybe try a narrower dish so you have greater topping depth. You need to make small holes in the crumble with e.g. the handle of a teaspoon, to let the steam out as it cooks.
Frequently asked Questions 🎓
Sugar attracts the moisture in the recipe, drawing it away from the flour and preventing the formation of gluten. ... However if too much sugar is present, the cake is so tenderised that gluten is unable to maintain the volume of the cake and it begins to crumble when cut..
Instructions
  • Peel, core, and slice apples into thin slices (approximately 1/8 inch). ...
  • Layer apple slices in pie shell (it will be really full) and pour any leftover juice over the apples. ...
  • Bake at 450 for 15 minutes, reduce heat to 350 degrees and bake an additional 45-55 minutes. ...
  • Serve warm or room temperature.
  • The difference between a Dutch Apple Pie (aka Apple Crumble Pie) and a traditional Apple Pie is the streusel topping that bakes up into crunchy, sweet deliciousness and is, in my opinion, easier to make than a pastry top. ...
    You don't use the right amount of butter: Not enough butter, and your topping will be a dry, floury mess. ... But if you feel your topping is still too dry and crumbly, (even for a crumble,) add a bit more melted butter, a tablespoon at a time..
    Cobbler: A cobbler is a deep-dish baked fruit dessert with a thick dropped-biscuit or pie dough topping. ... Crumble: Similar to a crisp, a crumble is a baked fruit dessert with a layer of topping. A crumble topping rarely includes oats or nuts, and is instead usually a streusel-like combination of flour, sugar and butter.
    I lay my topping out on a baking tray and toast it in a fairly hot oven. Then put it on the crumble fruit at the last moment and straight back in the oven. That way it doesn't get soggy.
    If you are making the crumble in advance, cover it with cling film and allow to cool to room temperature before placing in the fridge. When ready to cook, place the crumble in the preheated oven and bake for 30 minutes..
    A few more cooking questions 📍