Season the chicken generously with salt and pepper. Dredge in flour; shake off the excess. Brown in the hot oil, turning to brown all sides evenly. You are NOT cooking it through at this point but merely browning the chicken to form a crust that, later, will really add so much texture to the cooked dish. Remove the chicken from the pan.
To the remaining oil and drippings, add the chopped onion and garlic. Cook, stirring, for about a minute or until the onion pieces start to soften and turn translucent. Add the tomatoes, bell pepper and white wine. Boil gently for about two minutes. Arrange the chicken pieces in a single layer. Sprinkle the oregano leaves over them. Add the bay leaf. Cover the pan, lower the heat and simmer for about an hour. I do not recommend stirring.
When the sauce is thick, add the capers. Simmer, uncovered, until the sauce thickens some more and the mixture appears almost dry. Towards the end of cooking, add more salt and pepper, if needed. But if you seasoned your chicken well, there should be no need for additional salt and pepper as the white wine provides all the flavors the chicken needs.
Chicken cacciatore goes well with crusty bread, rice or pasta.
If you’re wondering what wine is best for cooking chicken cacciatore, I suggest fruity semi-sweet wines which will offset the sour notes of the tomatoes wonderfully.