Salt the meat on both sides. Let sit at room temperature for at least 15 minutes.
Heat a Dutch oven or large pot over medium-high heat.
Add oil to the pot.
Brown the beef, then the chicken.
Cook together for about 6 minutes.
Add the sausage and cook for another two minutes.
Remove the meats and set aside.
In the same pot add the sofrito, garlic, cumin, paprika, oregano, and sazon.
Sauté until fragrant, about a minute.
Add the onions and cook for about 5 minutes.
Pour in the water or broth.
Return the meat to the pot and bring it to a boil, lower the heat, and simmer for 15-20 minutes.
Add the root vegetables, starting with the one that needs the most time to cook – in this case, green plantains.
Cook for about 10 minutes before adding the yuca, squash, potatoes, and corn.
Continue simmering the stew for about 10 minutes until the meat and veggies begin to soften.
Season with salt, pepper, and other seasonings to taste.
Continue cooking until root vegetables are tender. The stew should be thick and hearty; if not, mash a few root vegetables to thicken it.