I love the dumpling kitty pattern and had to try making a tuxedo kitty with it!
Pattern: Dumpling Kitty (Ravelry link - only available if you’d already saved it)
Yarn: worsted weight acrylic in gray & white
Hook: 3.5 mm (E)
For the color changes, I found a tutorial (youtube link) for a way to different way to change colors, so I had to try it out.
I remade the white patch a few times trying to get it right. One of the first attempts:
I eventually got a version that wasn’t too bad! Not perfect, and there are a few things I’d change if I made another one, but it turned out ok!
I had to give the kitty little white socks on their feet and a white tip on the tail. 
