To make the dressing, whisk the ranch with sour cream and mayo until well combined. You can also add some herbs if you like.
In a large bowl, add the crumbled or cubed cornbread, beans, corn, green onion, bell pepper, tomato, and cheddar. Mix until well combined. Then add the dressing, and mix until everything is well combined. Have a taste and adjust seasonings to your preference.
I recommend allowing the cornbread to sit at room temperature for at least 4-6 hours after it's baked and before it's added to the salad.
Chill the salad in the fridge for at least 2 hours before serving, to allow the flavors to settle.
Store the salad in the fridge for up to 3-4 days. Be aware that the cornbread will become super moist and maybe a little bit mushy, so if you don't like that then don't mix everything together (cornbread, salad, and dressing) before you're ready to serve.