Toss shrimp with spice blend and set aside. Heat olive oil in a large skillet over medium high heat. Add shrimp and cook, tossing occasionally for 3-4 minutes until shrimp just begin to turn opaque. Add in the chimichurri sauce, and toss until the shrimp are evenly coated.
Cut 12 mini round corn tortillas with 3-inch round cutter (if desired, stack 2 or3 tortillas to cut).
Heat the oil for frying into a large skillet (about 2 inches in depth) to 375ºF. Add the tortillas, one at a time, and fry until golden brown and crispy, about 1 ½ minutes. Using tongs, transfer to a paper towel-lined pan and sprinkle with additional chili lime seasoning. Set aside.
To serve, divide the shrimp mixture between the mini tostadas. Top each with a spoonful of fresh guacamole and sprinkle with queso fresco and cilantro.