By Cari Shane Did you know that you really only need one kind of knife to do most of your cooking? And those other knives — the ones that come in that big block, taking up all that room on your kitchen counter: “Unnecessary,” says Derek Swanson, co-owner of District Cutlery, a verified Service Disabled Veteran Owned Business, which sells hundreds of knives from all over the world. Swanson owns the shop with his brother, Ryan, a master sharpener. We sat down with Derek Swanson at his Union Market shop and asked him tons of questions to hone our knife knowledge. This is what we found out. What’s…