Add olive oil to a sauté pan or nonstick skillet and heat over medium-high.

Slice cheese into four 1-ounce slices, placing 1 ounce onto each of 4 slices of bread. Add 1/2 cup spinach to each.

Place 2 slices of turkey on top of the spinach, then cover with remaining slices of bread.

Spray bread with cooking spray and place sandwiches on the heated pan. Cook on each side until golden brown and cheese is melted.

Serve plums on the side.