Remove sausage from the casing & combine both meats in a bowl. Add the remaining ingredients & mix well. Let the mixture rest in the refrigerator for at least 1 hr for seasonings to work .
Form hamburger patties as usual & make them about 3/4 larger than the bun. The burgers will shrink, so doing this will give you a bun-fitting hamburger patty.
Cook hamburgers on high heat on ea side for about 1 minute. Then finish them on a med low heat till done (An internal temp of 160F is recommended by the USDA).
When done, spray them on both sides w/a water mist & sprinkle a little salt on them. Serve immediately.
If not serving immediately, put the patties in a pan w/only enough water to cover the bottom. Keep them covered so they don't dry out. Doing all of this will give you a slightly moister hamburger patty.