I have an undermount sink that is currently grouted in with bullnose tile. The grout is about 1/4 - 1/2" thick. I have removed most of the grout, as it was cracking and chunks were falling off. Should I regrout or should I caulk with Polyblend caulk? Do I need to get all of the grout out? Or will the caulk stick if I got most of the grout out? TIA

It would be best if all grout is removed. Then install the blended caulking. This will make cracking minimum.

Chuck

If you use caulk, you will need to use thin layers as 1/2" at one time is not good practice. You might want to consider backer rod. You could use sanded grout, that will fill 1/2" better.