Bring water (and milk, if using) to a boil. Slowly whisk in polenta. Reduce heat and simmer, stirring often, until creamy (5–10 minutes). Stir in butter and parmesan. Season with salt.
In a large skillet, cook pancetta until crispy. Remove with a slotted spoon and discard half the rendered fat. Add a bit of olive oil to the pan if needed.
Add broccoli planks in the skillet and sear until nicely browned, about 2 minutes.
Clear the center of the pan and add green beans and slivered almonds.. Sauté for one minute then toss with the broccoli. Clear the center of the pan again and add the shredded cabbage. Sauté for one minute and then toss the mixture together, season with chili flakes, black pepper and salt. Add the garlic and 1/2 cup water and cook until the vegetables are crisp yet tender, about two minutes.
Add pancetta back in, toss everything together, and season with a few drops of balsamic vinegar. The flavor should be salty, tangy and spicy.
Spoon polenta into bowls and top with the stir-fry. Finish with grated cheese and enjoy.