Remove the stem, seeds and veins from jalapeno pepper. Or leave the seeds and veins in for some good heat. Cut the jalapeno and half and with skin side up, with your hand flatten the pepper so it will roast in the fry pan.
Heat a 10 inch non-stick skillet over medium high heat. Lay in the garlic, jalapeno and the halved tomatillos. The tomatillos should be cut side down.
When the tomatillos are well browned (3-4 minutes) with tongs, turn everything over and brown the other side. The tomatillos should be soft.
Scrape the tomatillos, jalapeno and garlic into a food processor and let cool to room temperature.
Add the cilantro, sugar, vinegar, Pickapeppa and water. Blend to a coarse puree, easily spoonable consistency.
Pour into a salsa bowl and add the diced onion. Note, Once the onion has been diced, put it in a strainer and rinse under cold water. This will temper the onion flavor.
Add and season with a little salt and a little more sugar if you wish.