Beef Steak, Roasted Vegetables, and Toasted Buckwheat Stew

Conceived and prepared February 14, 2011. Based on leftovers from Sunday night's Valentine Day supper.

2 T butter
2 T EVOO
1 c tender-shredded rare grilled boneless beef steak (see Note)
1 c roasted mixed vegetables, coarsely chopped
1 medium white onion, thin blossom cut
2 ribs celery, 1/2 inch cross cut
1 T garlic, minced
2 T tomato paste
2 c prepared kasha (Wolff's® toasted buckwheat)
1 14 oz can beef stock, heated
2 c beef base (hot water plus 2 T McCormick® concentrate) or use another can of stock
2 T tapioca starch in 2 T water

In a 4 qt saucepan, heat the oil and butter until bubbling stops. Add celery, and cook a few minutes. Add onions, and cook until beginning to color. Add the garlic, and clear a spot to add the tomato paste. When bloomed, mix into onions, and stir in the kasha. When heated through, add the vegetables, and then the hot stock and beef base. Bring to a simmer, add the starch suspension, and the shredded beef. Cover and simmer for 10 minutes. Serves 4 to 6.
Note: 
Prepared from charcoal-grilled boneless eye of the rib. Cut match-stick shreds with a sharp chef's knife across the muscle fibers to produce tender beef.