Prepare a charcoal grill by lighting charcoal and letting it burn until it glows bright orange
, ashes over, and is very hot. Brush the grill grate
generously with oil.
Meanwhile, put the ostrich meat in a mixing bowl, sprinkle generously with salt and pepper, and form into 4 equal-size patties about 3/4-inch thick. Grill
the burgers, turning once, until medium-rare, about 3 minutes per side. Remove from the grill and let stand for 5 minutes.
Spread 1 tablespoon of the yogurt on each of 4 muffin halves, and 1 tablespoon mustard on each of the remaining muffin halves. Place the burgers on the mustard-coated muffins; top each with a slice of tomato, lettuce, and a generous pile of pickles. Top with the yogurt-coated muffins and serve immediately.