In a small bowl, whisk together equal parts white wine vinegar, sugar, and salt until dissolved. Add the sliced jalapeños and cilantro, tossing to coat. Set aside for 15 minutes.

Combine chopped red onion with lime zest and juice in a large bowl. Massage for 2-3 minutes until tender. Let sit to soak up the flavors.

Cut cucumbers in half; smack to crack. Slice into 1-inch pieces, sprinkle with salt, and let sit for 10 minutes in a colander.

Heat olive oil in a saucepan over medium heat, add minced garlic and sauté until golden. Blend garlic and oil with pickled jalapeños, lime juice, vinegar, agave, miso, cilantro, and salt until smooth.

In the bowl with marinated onions, add drained cucumbers, rinsed beans, and remaining cilantro. Toss with dressing until well-coated.

Spread mashed avocados on tostadas and top with the salad. Sprinkle with pickled jalapeños for a delightful serving.

Store the salad in airtight containers for up to 4 days, keeping pickled jalapeños separate to maintain crispness.