Place the jalapeño, half of the chopped onion and the juice from the tomatoes in the can in a blender. Blend the mix until close to pureed. Remove from blender.
Place in a blender the tomatoes, black pepper, salt, cumin, garlic clove, onion powder, and garlic powder, along with the remaining onion. Pulse no more than 4 times to break up the tomatoes.
Add the two mixes together and stir.
Add chopped cilantro to taste. Add additional salt and pepper to taste.
Can be served right away, or for the best flavor, refrigerate at least one hour prior to serving.
Video
Notes
You can opt for more or less pureeing depending on the thickness of the salsa base you like.If you like your salsa chunkier, opt for a food processor instead of a blender.The longer you refrigerate, the thicker your salsa will become. Plus the spices will have more time to blend.