Cook cubed beef in beef broth until tender. Use a heavy Dutch oven or similar pot with a cover so you will not have to add more liquid. Remove meat from the pot and cool the broth.
In a frying pan fry the sliced bacon until crisp. Remove bacon and crumble but leave the drippings in the pan.
Add beef to hot drippings and cook, covered, for 5 minutes.
In a separate frypan make a roux with 1tablespoon bacon drippings and the flour. Stir constantly and cook to a golden brown. Whip the cooled broth into the roux, then whip in sour cream, lemon juice, lemon rind, sugar and tarragon.
Pour the lemon sauce on the meat, and place in a serving casserole. Sprinkle it with the crisp bacon.