Preheat oven to 425 degrees F. Spray cups of a 24 cup mini muffin tin or a standard size 12-cup muffin tin with nonstick cooking spray.: When the oven air warms and you hear the faint hum of the fan, the environment for crisping is ready. The preheated oven ensures the tortilla cups become uniformly golden rather than limp, because the sudden high heat rapidly evaporates surface moisture, creating crunch. You may smell a faint toasty scent as metal heats, which is normal. A common mistake is not preheating long enough, which can result in soggy or unevenly baked cups, so wait until the oven fully reaches temperature. Also, ensure the muffin tin is well sprayed to prevent sticking, because stuck cups can tear when removed.
To make tortilla cups: Using a 3 inch cookie cutter or cup, cut about 8-9 medium circles out of each tortilla. Brush each circle with olive oil or spray with cooking spray. Press each circle into a muffin cup. Bake 10-12 minutes or until cups are golden and crispy.: Using a 3 inch cookie cutter or cup, cut about 8-9 medium circles out of each tortilla. Brush each circle with olive oil or spray with cooking spray. Press each circle into a muffin cup. Bake 10 to 12 minutes or until cups are golden and crispy. : As you cut the circles, the smell of fresh flour tortillas is gentle and comforting, and brushing with olive oil gives a light sheen that deepens color as they bake. Press the dough firmly into the wells so the edges conform and crisp evenly; if left loose the cups may slump. During baking you'll notice the edges turn a warm golden brown and the centers tighten, a visual cue the cups are done. One mistake is baking too long thinking more crunch is better, which will burn the thin edges quickly, so check at 10 minutes and rotate the pan if your oven runs hot. Let the cups cool slightly to firm up before handling, because they continue to crisp as they rest.
To make guacamole: In a medium bowl, mash together the avocados. Mix in onion, tomatoes, cilantro, cayenne, salt and lime juice. Stir until fully combined, cover and set aside in the fridge until ready to use.: In a medium bowl, mash together the avocados. Mix in onion, tomatoes, cilantro, cayenne, salt and lime juice. Stir until fully combined, cover and set aside in the fridge until ready to use. : The aroma of fresh lime and cilantro will pop as you stir, and the mashed avocados should be creamy with a few small chunks for texture. Mashing by hand gives better mouthfeel than over-processing, and folding in the diced onion and tomatoes adds contrast. The cold fridge will slow oxidation and let flavors meld, producing a fragrant, cohesive mixture. A common pitfall is over-salting early; taste after chilling because flavors concentrate. Also be mindful that very ripe avocados mash smoother, while firmer ones yield chunkier guacamole, so adjust your technique to the fruit's ripeness.
To cook shrimp: Combine shrimp with taco seasoning in a large bowl or ziplock bag. Heat a large heavy-duty or cast iron skillet on high heat for 2 minutes. Add the olive oil and shrimp. Cook shrimp in a skillet on medium-high heat until pink and cooked through, about 5 minutes. Remove from heat and set aside.: Combine shrimp with taco seasoning in a large bowl or ziplock bag. Heat a large heavy-duty or cast iron skillet on high heat for 2 minutes. Add the olive oil and shrimp. Cook shrimp in a skillet on medium-high heat until pink and cooked through, about 5 minutes. Remove from heat and set aside. : When the skillet hits high heat it gives off a dry, metallic warmth and the oil will shimmer when ready, a sign you can add the shrimp . Tossing the shrimp in the seasoning makes their surface aromatic, and as they sear you should hear quick, light sizzling with a faint toasted scent. Watch the color shift from translucent gray to opaque pink for doneness, which keeps them tender and juicy. Overcrowding the pan can steam the shrimp instead of searing them, producing a rubbery texture, so cook in batches if needed. Also, avoid overcooking beyond the opaque stage, as they quickly firm up once done.
To assemble: Fill each mini tortilla cup with about 1 teaspoon of guacamole (use 2 tablespoons for regular size cups). Top guacamole with 1 shrimp and sprinkle with a squeeze of fresh lime juice. Serve immediately.: Fill each mini tortilla cup with about 1 teaspoon of guacamole (use 2 tablespoons for regular size cups). Top guacamole with 1 shrimp and sprinkle with a squeeze of fresh lime juice. Serve immediately. : The final assembly is a small theatre of contrasting elements, with the vivid green guacamole nesting inside the warm, brittle cup and the seasoned shrimp perched on top. Add a brief squeeze of lime for a bright citrus finish that lifts the richness, and you may notice the aroma freshening the plate. Serving immediately preserves the crispness of the cup; if you wait, moisture from the guacamole can soften the shell. A typical mistake is overfilling cups which can cause messy bites, so keep portions modest for tidy presentation and balanced flavor in each mouthful.
