Preheat a cast iron skillet over medium-high heat.
Grate half of a medium onion using the smallest holes of a box grater.
Measure two tablespoons of the grated onion, leaving behind any liquid.
Add the ground turkey, Worcestershire sauce, grated onion, salt, pepper, and Adobo to a bowl.
Mix the burger mixture well, trying not to overwork the turkey meat.
Divide the turkey into four equally portioned balls.
Heat a cast iron skillet over medium-high to high heat. Add a bit of oil and add the burgers. As soon as they hit the pan, smash the burgers flat using the back of a spatula.
Cook for about 4 minutes per side. Flip the burgers halfway through.
Meanwhile, toast the buns.
If adding cheese, add it the last two minutes of cooking.
Remove the finished burgers from the pan, measuring with a meat thermometer to ensure they have reached an internal temperature of 165 degrees Fahrenheit.
Build your burgers, adding your preferred toppings and condiments. Serve right away.
