Sounds like some of the lakes around where I live, basically featureless bottom filled in with muck and goose crap. I'd be around the deeper water and try and find and changes in the bottom both hard vs soft and any little bit of structure. If the lake/pond is somewhat managed there may be some sort of fish cribbing, rock piles, brush piles, tires and etc put in by man to give fish structure in an otherwise structureless lake. If its a public lake there may be maps of the lake online where the structure was added. I would look for structure first and then look for changes in the bottom hardness starting out in the deepest spot on the lake. Fishing the during softwater season with a decent depthfinder will help you find good places also.