For many years my friends in KL would visit the same thunder tea rice hawker. It's called lei cha fan because the Chinese character for thunder 擂 means "to pound" in Hakka, which is how the tea sauce is made. This particular hawker was very well known and did good business, but about six months ago he got fed up living in the big city, packed up his bags, and moved home to the boonies, somewhere between KL and Ipoh.
Thankfully my friends stayed in touch with him, and since we planned to go to Ipoh, we decided to visit him. After driving an hour or so north we pulled off the highway, and after several wrong turns in the kampung and some bemused looks from the locals, we found him.
He now operates out of a stall on the side of the road. I can't be more specific than to say that he stands under a tree, across from a green warehouse and a temple. I did look at the map on my phone, but it was useless - google didn't show a road anywhere in the area. But he's very well known; even people in Ipoh knew of him, so I imagine if you asked around people would be able to direct you.
He and his wife make everything, and he has a very limited supply. He makes only enough to cover his living expenses, and no more.
The rice and vegetables are prepared at home and packed. You can see the containers stacked on the table in the attached photos. When you order, he ladles on the tea sauce, adds hot water if desired, and sprinkles on peanuts.
Everything is fantastically fresh and crisp. I've heard tea sauce described as quite grassy, or too medicinal, but I found this very smooth and mild, and incredibly moreish - I was skimming sauce from my friends containers. The chives and tofu were wonderfully crisp, and the rice was beautifully light and fresh. I had it with the hot water, which made it fragrant and also easier to mix.
Highly recommended if you can find him :)