Rules of Double Choco: (copied from here)
- Divide the grid into regions by drawing along some of the dotted lines.
- Each region should have one group of gray cells and one group of white cells; both of these groups should be connected.
- The two groups in a region should be the same size and shape (but they may be rotated or reflected).
- Each number tells the size of each of the groups in its region. Not every region needs to have a number.
Because my username contains three B's (one in uppercase and two lowercase), here's a puzzle containing the three letters "Bbb". Enjoy!
You can solve it online on Penpa.