Sharp Cheddar and Mustardy Greens Breakfast Sandwich

INGREDIENTS

• 1 tablespoon heavy cream
• A knob of butter
• 1 tablespoon grainy mustard
• 4 eggs
• 4 biscuits from your favorite recipe (or 4 English muffins, or 8 pieces of toast)
• 4 slices of good sharp cheddar
• 1 tablespoon olive oil
• 1 bunch of Swiss chard, washed, stems removed, and cut into 1-inch square-ish pieces
• Salt and pepper