Pork Medallions With Pears without fish cutlets

1 tablespoon fresh coarse ground black pepper 1 1/2 lbs pork tenderloin, cut into 1-inch-thick medallions 4 tablespoons butter 1 cup chicken stock 1/4 cup[...]

2 tablespoons butter , divided 2 tablespoons olive oil , divided 2 cups chopped leeks (white and pale green parts only, about 2 med.) 1 cup low sodium chicken[...]