Spray Pam on your grill grate and turn the grill to the highest heat available.
Slice the tomatoes, shallots, and jalapenos in half lengthwise.
Remove the root from the onion and slice it in half.
Carefully place the tomatoes, shallots, jalapenos, and onions on the hot grill. Close the grill.
After a couple of minutes open the grill and flip the veggies over.
Remove to a bowl or platter when they are well charred.
Add the charred veggies to your food processor and pulse a couple of times.
Add the cilantro, salt, and juice from the limes.
Pulse until blended as well as you like.
Add additional lime and salt as you prefer.
Serve immediately or store in the fridge until ready to serve.