Baking Step:

1. For the crumble, put all ingredients together and mix well. It is not necessary to form a dough.
2. Refrigerate until firm and crumbly.
3. BFor the muffin, using a paddle attachment, mix the egg, milk, and oil at low speed for 1 minute.
4. Scrape down the bowl and add the muffin mix, butter, and salt. Mix for another 2 minutes at medium speed.
5. Deposit the batter into paper cups or muffin molds until 1/3 full. For standard muffins, the batter weight should be about 70g, and for jumbo muffins, it should be about 90g-100g.
6. Sprinkle the crumble on top of the muffin batter.
7. Bake at 180°C for about 30 to 35 minutes. Baking conditions may vary depending on batter weight and oven characteristics.
8. Remove from the oven and let cool before serving.