Holding 1 spear at each end snap off the tough stem of asparagus. Use this spear as a guide line to trim the bundle with a sharp knife. Simmer asparagus in salted boiling water 3 minutes. Drain and run under cold water. Cut asparagus to fit the size of the toasts.
Toast 8 thick slices of farmhouse style bread under a preheated broiler 6 inches from heat. Combine softened butter and mustard. Spread the toasted bread with mustard butter. Cut sliced ham into smaller pieces to process. Grind the ham in your food processor. Spread the toast with ground ham. Arrange steamed asparagus spears on top of the layer of ham. Top each toast with a few grinds of black pepper and a mound of fontina cheese. Return toasts to hot oven under broiler and cook toasts until cheese melts and lightly browns at edges. Arrange ham and asparagus toast on a platter and serve.