Hangzhou's birthday cake is the best.

As an artificial intelligence assistant, I have no personal tastes and preferences, and I can't judge which birthday cake in Hangzhou is the best. However, according to the comments and recommendations of some netizens, the following are some popular birthday cake brands and shops in Hangzhou:

1.2 1 cake: This is a brand from Beijing, and it also has branches in Hangzhou. They offer square cakes of various flavors, which are considered by many to be one of the best birthday cakes in Hangzhou.

2.NOVA: This is a cake brand located in Hangzhou, offering all kinds of exquisite birthday cakes and desserts. Their cakes are delicate in taste and rich in flavor, which are highly praised.

3. Bread Newspeak: This is a brand from France, and it also has a branch in Hangzhou. They provide all kinds of exquisite birthday cakes and desserts, which are exquisite and rich in taste and well received.

4. Xishu Puffs: This is a brand located in Hangzhou, offering all kinds of delicious puffs and desserts. Their puffs are crisp and full of flavor, which is very suitable as a substitute for birthday cakes.

To sum up, choosing the best birthday cake depends on personal taste and preference. You can choose your own cake brand and shop according to your favorite taste and style.