Yeah, bread can get complicated depending on what you want to make. Excluding flour, I have in my pantry to make bread these:

• espresso powder
• cocoa powder (multiple varieties)
• barley malt syrup
• oats
• variety of seeds (shitload of carroway mainly)
• variety of spices
• variety of nuts
• variety of oils/fats (olive oil, peanut oil, ghee, sticks of butter, etc)
• Baking powder
• Baking soda