Pat your cooked shrimp dry with a paper towel and cut them into bite size pieces. Then add them to a mixing bowl and set aside.
Next, add the quartered tomatoes, chopped cilantro, chopped jalapeño (if using), diced avocado and salt to the bowl with your shrimp.
Freshly squeeze the lime and mix until the salad is completely coated. Taste and adjust your salt and lime juice accordingly.
Make the avocado mash by mashing the avocado with lime juice and salt until smooth texture forms.
To serve, add a spoonful of avocado mash to the tostada, then add a few spoonfuls of the shrimp salad on top. Top with any additional cilantro and enjoy.
Notes
If you're using frozen pre-cooked shrimp, make sure to thaw your shrimp completely before cutting and adding them to the bowl.
You can make the salad ahead of time and let it chill in the fridge for 30 minutes – 1 hour before serving.
Alternatively, you can serve the shrimp salad with your favorite tortilla chips.