Cut pork loin into 1/2-inch slices.
Place flour in a shallow dish.
Season pork medallions with salt and pepper, then place in flour and coat evenly on both sides.
Melt 2 tablespoons butter in a large skillet over medium-high heat.
Add pork and cook in batches for 2-4 minutes per side, or until golden, adding more butter as needed.
Remove pork to a covered platter to keep warm.
Add cream and pesto to skillet; mix well.
Add tomatoes and cook 3-5 minutes, or until thoroughly heated.
Pour over pork medallions and serve.
