Sprinkle chops with salt and pepper. Put a large skillet over medium-high heat for 2 minutes. Add olive oil; when hot, add chops and turn heat to high. Brown for 2 minutes on each side.
Reduce heat to medium. Add water or wine and garlic and cook, turning chops twice, until the liquid has almost evaporated -- 3 minutes. Add stock, turn heat to low, and cover, cooking until chops are tender but not dry, 10 to 15 minutes. (When they're done, their juices will run slightly pink.)
Transfer pork to a platter and cover to keep warm. Pour off liquid and add 1 tablespoon butter and 1/4 cup minced shallot to the pan. Cook over medium heat until the shallot softens, 4 minutes. Add 1/2 cup stock or water and cook, stirring, until syrupy, about 5 minutes. Add 1/4 cup chopped fresh tarragon and stir. Add 1 tablespoon more butter and 1 tablespoon lemon juice, swirl, and pour over the pork. Serve garnished with a sprinkle of chopped tarragon. Makes 4 servings.
