Challah for Parashat Shlah
Every week, Julie Seltzer, artist and Torah scribe, bakes a challah depicting an aspect of the week's Torah portion.
They should make fringes on the wings of their garments for all generations, and the fringe of the corner should have a thread of tekhelet.
וְעָשׂוּ לָהֶם צִיצִת עַל-כַּנְפֵי בִגְדֵיהֶם, לְדרתָם; וְנָתְנוּ עַל-צִיצִת הַכָּנָף, פְּתִיל תְּכֵלֶת
These are tzitzit challot. As you can see, there is one blue string, the tekhelet--given its color from purple cabbage.