For the ribs: Put the flour in a pie pan, add the salt and pepper and mix. Dredge the ribs in the mix and set aside on kitchen paper.
Set a 6-quart multi-cooker to the saute setting on high. When hot, add the bacon and cook until crisp, about 5 minutes. Remove the bacon to a plate. Remove 2 tablespoons of the bacon grease and set it aside for the collards.
Working in batches of 3 to 4 ribs at a time, brown the short ribs on all sides, using the olive oil if needed. Set aside.
Add the carrots, celery and onions to the pot. Add the garlic and tomato paste and mix.
Return the ribs and bacon to the pot. Deglaze with the wine, making sure to scrape up the brown bits with a wooden spoon. Add the rosemary, thyme and bay leaf. Cover and cook on high pressure for 40 minutes. Switch the pot to vent and allow the pressure to release, 4 to 10 minutes.
For the collards and peppers: While the multi-cooker is venting, start on the collards. Heat the oil and/or the reserved bacon grease in a large skillet and cook the peppers and onions until soft and slightly browned.
Meanwhile, remove the stems and ribs from the collards. Add the collards to the pan and season with salt, pepper and red pepper flakes. Saute until tender, 6 to 8 minutes.
Remove the ribs from the pot. Strain the sauce through a mesh strainer into a large measuring cup; discard the vegetables in the strainer. Add a splash of red wine vinegar to the sauce and adjust seasoning as needed.
To serve, put the collard greens onto a large platter. Add the short ribs and some of the sauce. Garnish with parsley.