Chicken | Add the chicken thighs into a bowl. Add lime juice, soy sauce, fish sauce, sriracha, sugar, salt, pepper, and garlic. Mix well. Allow the chicken to marinate at room temperature for 10 minutes. Heat a pan over medium-high heat. Once the pan is hot, add a generous amount of oil. Once the oil is hot, add the marinated chicken thighs to the pan, spacing them out evenly. Cook the both sides until an internal temperature of 165°F / 78°C is reached.
Assemble | Spread mayonnaise on both sides of the baguette. Add the sliced chicken, Vietnamese pickles, cucumbers, cilantro, and jalapeños on top of one half of the baguette. Place the other half of the baguette on top of the fillings, press down gently to compact the sandwich, and slice it into smaller pieces if desired. Serve immediately and enjoy!