Chop the cauliflower as small as you can. You could use a food processor and just pulse it.
Put it in a large bowl and add the quinoa, onion, carrot, and slices of the jalapeño.
In a separate bowl mix the lemon juice with olive oil and salt. Pour over the mixture of cauliflower and quinoa. Mix well. Add herbs, mix and test. Adjust the seasoning if necessary.
Serve on top of corn toast and finish it with slices of avocado.