Combine yeast, water, and sugar in a large mixing bowl, stirring until yeast and sugar dissolve. Let stand 5 minutes or until bubbly. Stir in shortening and salt. Add flour, 1 cup at a time, stirring to form a stiff dough.
Turn dough out onto a floured surface; knead 10 minutes or until smooth and elastic. Place dough in a greased bowl, turning to grease top. Cover and let rise in a warm place (85°), free from drafts, 1 1/2 hours or until doubled in bulk. Turn dough out onto a lightly floured surface; knead 10 minutes.
Divide dough in half; shape each half into a long, thin loaf. Place loaves in well-greased baguette pans that have been sprinkled with cornmeal. Cut 3 or 4 diagonal slashes, 3/4-inch deep, in top of each loaf. Brush loaves with water. Leave uncovered, and repeat rising procedure, 1 hour or until doubled in bulk. Brush risen loaves with water.
Place a shallow pan of water on bottom oven rack. Bake loaves at 400° for 15 minutes. Reduce heat to 375°; continue baking 25 minutes or until loaves sound hollow when tapped. Remove bread from pans immediately; cool on wire racks.