Have you had any plumbing work done recently, especially by a DIY'er? I ask because, I have seen in the past, issues with water flow when add-on work has been done on plumbing wherein a plumber/DIY'er uses bread to keep water back from a joint to be sweated. Once the joint is done and the water is turned back on, the bread rushes to the faucet and can clog the aerator.

Or maybe it is something else entirely. ;)

If your faucet is cheap or old, get a new faucet. It sounds like the pressure balance is failing. You have a single handle control, right? Get one with separate hot/cold faucets. If there are pressure fluctuations in your hot/cold plumbing, the separate faucet controls will help, if you choose to get a cheap replacement faucet. If you want a single handle control, make sure it has a pressure balance mixing valve. It will cost more $ for a quality one.

The reason I think your hot water is "cutting out" is that cold water is forcing its way back through the faucet and up into the hot water pipes. This can happen if your hot water has lower pressure than cold and the single handle faucet has a faulty pressure balance.

I did do some plumbing work, but that was more than 3 months ago. Could the bread still be the issue?

The kitchen has a single handle control (probably cheap) but the bathroom, which also has the problem sometimes, has two "regular" turn knobs.
When the water stops, no water flows at all...neither hot nor cold.
It does make a clonk sound when the water stops, but not very loud.
A few months ago, it made a much louder sound and it appeared to be further down the pipes.
Thanks again!

Are there any one way valves in your plumbing system? hot water recirculation system or water softener? Do you have well water or a pump?

I don't think there are any one way valves.
I have a "regular" electric water heater.
I'm on public water, in Seattle, WA.

Thanks!!!!

May have debris in the plumbing. Unscrew the aerator from the sink faucet and flush the lines.

Ok, I'm not sure if this easy fix actually solved the problem or not, but I turned the hot water shut-off valve to its maximum opening, and the water flowed well after that. I only tested for a few minutes, but at least it improved it quite a bit.

I'm crossing my fingers that this will take care of it.
I've read about dishwasters and water stopping hard, which sometimes makes noice. I guess some sort of air-trap will take care of that...

I will also try to flush the lines by unscrewing the aerator...if I can figure out how.

Thanks VERY MUCH!!!!