• Preheat oven 375 degrees.
• Place the corn and jalapeño on a sheet pan. Drizzle with 2 tablespoons of olive oil and toss to coat evenly. Slide the corn and jalapeño to one side of the sheet pan, making room for the onions. Place the red onion on the sheet pan and drizzle with the remaining 1 tablespoon of olive oil. Season with salt and pepper.
• Transfer to the oven and roast until onions are tender, about 10 minutes. Remove the onions from the sheet pan and set aside. Flip the corn and jalapeño so that they will cook evenly and return the sheet pan to the oven and roast until jalapeño is charred on all sides, about 5 more minutes. Remove the jalapeño and set aside. Turn the oven on broil and place the corn back into the oven on the top rack. Finish the corn under the broiler until a nice char has formed, about 2 minutes, watching carefully so it doesn't burn!
• Remove the corn from the oven and set aside to allow to cool.

Make the Seared Chicken:

• Meanwhile, pat dry the chicken breast. Using a meat mallet or the bottom of a skillet, pound the chicken until it is an even 1/4 inch thickness. Season with salt, pepper, cumin and chili powder on both sides.
• Heat a large skillet, preferably cast iron, over medium-high heat with olive oil. Sear the chicken until golden brown and cooked through, about 4 minutes per side.
• When the chicken is cooked through, transfer to a cutting board to allow it to rest while you prepare the corn salsa.

Make the Corn Salsa:

• In a large bowl, add the mayo, lime zest, lime juice, garlic, cumin, chili powder, salt, pepper and cilantro. Stir to combine.
• Carefully cut the corn kernels off the cob and remove the seeds from the jalapeno. Finely dice the jalapeño and red onion. Add the jalapeno, red onion and corn to the mayo mixture. Gently toss to combine.

Build the Tacos:

• Slice the chicken into thin pieces. Serve on a warm tortilla with sliced avocado and fresh corn salsa. Top with freshly grated queso fresco, hot sauce (if desired) and serve with fresh lime wedges!