All other parts of my house has good hot water pressure, except the kitchen sink.. what's wrong?

You have some trash that's clogging the hot water inlet port in your faucets cartridge. The solution would be to shut the water off and open up the valve. Pull and clean the inlet ports on the cartridge. While you have the valve open turn the water back on to flush the supplies. You should have a strong hot water stream when you do this. If so then reassemble the valve. Good luck, Tom