I really wish
C@H would not take Cuban recipes and convert them to hot/peppery Mexican style recipes. This recipe is flank steak with tomatoes, peppers and onions and bears no resemblance to the Cuban dish that also uses flank steak and bell pepper. Poblanos, jalapenos, red pepper flakes and cilantro are not part of Cuban cooking. You get a completely non-Cuban flavor profile when you add hot peppers and cilantro to food.
The idea of making it in a slow cooker is a good idea. It appears that this is an attempt to recreate Ropa Vieja which is typically made with leftover flank meat that has been used first to make soup. The cooked meat is then repurposed by adding a sofrito with bell peppers, garlic, onions, dry sherry and tomato sauce, and it is served over white rice. My favorite recipe for this uses braised flank (which can be made ahead (fridge or freezer) since I don't use flank for soup. Personally, if I was going to convert it, I'd use a pressure cooker rather than a slow cooker since I always prefer food cooked in the former.
Sorry about the rant, but to me, this recipe shows once again, a lack of respect (or perhaps understanding) for Cuban culture.
C@H does not add hot peppers to Bolognese sauce or to Beef Bourguignonne. If anyone is interested in typical ingredients I'd be happy to post my favorite recipe.