The biggest problem with making bread after the apocalypse has to be the availability of ingredients. This is the part where gluten-free bakers get to jump up and shout hooray, because they have probably already been making potato bread and cassava bread for some time. Of the grains that do grow here in Central Florida, perhaps amaranth and sorghum might be our best choices. Research should be done into kenaf and durum semolina also. Assuming you'll be able to acquire some kind of flour or substitute...
Many preppers foresee themselves culturing sourdough starter to make homemade breads at some point in the future. After maintaining a starter for several years, I now no longer do so because I don't have a large enough family to properly produce and use almost any quantity of starter. It also takes a lot of cleaning and attention to bacterial growth prevention. Here in Florida, the warmer temperatures in your average air-conditioned kitchen will make your starter 'grow' about three times as fast as the yankees' starter. A sourdough starter gone flat can still be used in your bread recipes with the addition of either commercial yeast or a pinch of baking soda.
What can be used to leaven bread when you can't get baking soda? Hardwood ashes, once leeched and turned into lye (potassium hydroxide), can further be dehydrated and kiln-fired into potash/pearlash. Potash is potassium carbonate, known commonly for its fertilizer properties. It was an American tradition with some Native Americans and the colonists to leaven bread with potassium carbonate, but over time this fell out of favor when commercial baking soda (sodium bicarbonate) became available, as it has less of a bitter aftertaste. It is conceivable that the underground kiln your buddy used for making biochar was also making some pretty high-quality pearlash, or could be used to produce some.
For the easiest Solar Cooker ever, used to bake bread in along with an oven bag, check out this design that I have used successfully.
For other ideas on cooking with your preps, with local ingredients, and without expensive ingredients, please check out the labels marked Pantry Raid or Cook With Your Preps in the sidebar.