To make BBQ ribs in the oven, preheat it to 300 degrees Fahrenheit. Rub the ribs with spices and seal them in a foil packet. Bake for 3 hours, or until the meat is tender. Brush the ribs with barbecue sauce, and cook until the sauce thickens.
Rub the ribs with your favorite pre-made spice mix, or make your own by combining salt, ground pepper and celery salt. Alternatively, mix paprika, cayenne pepper, black pepper garlic powder and onion powder. Add in salt, oregano and thyme. Adjust the mixture to taste.
Make the foil packet by placing a large sheet of foil on a baking sheet. Fold two sides up and bend them together until they form a tight seal. Seal the remaining two sides to close the packet.
Test the ribs with a fork after 2 1/2 hours. If the meat is tender, remove the ribs early. If not, continue baking, and check for tenderness every 10 minutes.
When applying the barbecue sauce to the ribs, brush it over the side with the most meat. Use a pastry brush for easy application; a large spoon also works, if you do not have a brush. Return the ribs to the oven, leaving the packet open. Watch the sauce carefully to avoid burning.