Rinse, dry, and season bison with salt and pepper and set aside. Ensure all vegetables are prepped and that all other ingredients are gathered and measured.
Place pot on the stove over medium-high heat. The pot must have a tight-fitting lid, which will be utilized later. Once hot, add the olive oil and gently place the bison in the pot. Sear on all sides until nicely browned. Remove bison from the pot and set on a plate to cool.
Preheat oven to 350 degrees.
When to bison is cool enough to handle, completely coat the bison with half of your tomato paste. Heat the pot again and return the bison. Moderate the heat carefully and turn the bison slowly. The tomato paste contains a lot of fruit sugars, which will start to stick and caramelize. The goal is to
pincé the tomato paste, which will give your dish a beautiful mahogany color and add depth to the flavor. Be very careful to not burn the paste. Once the tomato sauce has caramelized, remove the bison again.
Work quickly as you complete this next step. Turn the stove’s heat down to medium. Immediately add the vegetables, dry spices, half the parsley stems, and remaining tomato paste to the pot and sauté, stirring vigorously. Once the mixture is coated and the bottom of the pot has that rich pincé color, increase the heat. Add small amounts of wine, gradually, while scraping the sauce from the bottom. Bring the wine to a boil to ensure all alcohol is cooked off.
Snuggle the bison into the pot. Add the beef broth so that the liquid covers ¾ the height of the meat and place bacon strips across the top of meat. Cover the pot with a tight-fitting lid and place on the middle rack. Braise the bison for 3-4 hours. It will be done when it’s fork-tender.
Remove the bison from the pot and let it rest while you finish the sauce. Strain the braising broth and return it to the pot, discarding its remaining cooked vegetables. Simmer.
In a separate bowl, slowly stir about a half a cup of cold water into your flour, smoothing out any lumps until it has the same consistency of heavy cream.
Pour the flour mixture through a fine mesh strainer and into the simmering braising liquid, whisking as the flour and water slurry is added. Simmer for 10 minutes, stirring occasionally to ensure it does not stick and burn on the bottom. Adjust the consistency by adding water if it is too thick. If it is too thin, add more of the flour mixture. Salt and pepper to taste. Remove the sauce from heat and whisk in the butter.
Slice the bison against the grain and place on a serving platter. Top with gravy mixture and garnish with the lemon zest and parsley.