To make Mexican Spice Blend, combine all spices and herbs in a resealable jar; whisk thoroughly with a fork to combine. Seal, label, and date. Mixture will keep well in a cool, dry place 6 months to 1 year.
Preheat oven to 425 degrees F. Line a rimmed baking sheet with parchment paper.
In a large bowl, toss carrots with olive oil and spice mixture. Spread out on prepared baking sheet and roast 20 minutes or until carrots are tender with golden brown edges. Scatter cherries and pepitas on hot baking sheet and gently toss. Set aside to cool.
Cut avocado into generous 3/4-inch chunks. Drizzle with lemon juice and a pinch sea salt. Add avocado and mesclun to carrots and toss gently. Finish with another squeeze of lemon and pinch of sea salt.
Serve salad at room temperature directly from baking sheet.