Q: Why did the baker go to the bank?
A: He need some dough!
Explanation: There is nothing better than fresh baked bread! The smell is amazing and, if you can eat bread, the taste is divine.
A person who puts bread or cookies into an oven is called a baker. Before you can bake some bread you need to mix it up. That mix is called dough; it can be cookie dough, or bread dough, or whatever type you are making.
Dough is also another word for money. (Keep in mind that it is an informal word.) If you need some money, you might go to the bank; you might ask you friend to lend you some dough for the weekend.
This joke is funny because it plays with the word dough: the mix you make for baking bread or another word (informal) for money.
Here is Jaime Oliver teaching us how to make fresh bread. Feel free to turn on the CC (closed captioning) or slow him down because he talks a bit fast.