Grill or broil beef, 4 to 5 minutes per side for medium-rare, turning once. Let stand 5 minutes; cut into thin slices. Mix with barbeque sauce and keep warm.

 

In small bowl, crush saffron threads into powder. Stir in lemon juice; let stand to soften.  Whisk potato pearls into boiling water. Stir in saffron mixture and salt; keep warm. Steam tortillas to warm and soften.

 

For each serving, lay 1 tortilla on flat work surface and spread with 3 oz prepared potatoes. Top with 1/2 cup spinach leaves and 2 to 3 oz barbeque beef. Top beef with 1 Tbsp each of cilantro leaves and raisins. Roll tortilla to close. Hold wraps in steamtable pans (wraps can be enclosed in foil or paper to go).