In a small saucepan, add 3 tablespoons of oil, followed by garlic, bacon, and salt. Sauté for about a minute until fragrant, being careful not to let it burn. Set aside.
Cut each plantain into about 4-5 thick slices.
Soak the slices in salted water for about 15-30 minutes, then remove and dry with a paper towel.
Pour vegetable oil into a large saucepan until it is at least 1-inch deep. Heat on medium heat until the oil reaches 375℉/190℃.
Gently place the plantains into the oil. Fry them in batches so that you don't overcrowd the pan.
Fry for 3-4 minutes until lightly brown on each side.
Use a large, slotted spoon or a similar utensil to remove the plantains from the oil. Then drain them on a paper towel.
Place about a ½ teaspoon or more of the garlic, oil, and bacon mixture into a mortar and give it a smash with a pestle.
Add the chicharrones and some salt if necessary. Then, one by one, start adding and smashing the fried plantains with the other ingredients. Once all the ingredients have just come together, and the mortar is nearly full, the mofongo is ready. Don't overdo it!
Run a knife or spatula between the mofongo and the mortar walls and place shrimp sauce in the middle.
Serve right out of the mortar or turn the mortar upside down on a serving plate and bang lightly - you will get a nice mofongo dome.
Repeat the same process with the remaining garlic, bacon, oil, and plantains.