Pulverize first 7 ingredients in blender. If sauce is too spicy for your taste, add additional small amount of orange juice and sugar to diminish the "heat". Add chopped cilantro after other ingredients blended so that the cilantro retains leafy appearance. Marinate chicken breast for 1 hour - do not marinate too long or the meat will get soft and start to cook because of the acid in the lime juice. Grill chicken breast until they have nice grill marks and are just done. Salt meat to taste. Cut slices on bias for presentation.
Mango Chutney: Cut mango into bite size pieces, about 1/2 to 1-inch long. Reserve any mango juice for the mixture. Place all ingredients in an 8 to 10-inch frying pan and simmer on low to medium heat for 15 minutes. Stir frequently to avoid burning. Remove from heat and when cool place in covered container and refrigerate for at least 2 hours. Keeps for at least 4 to 5 days. Best served slightly chilled.
Tortillas: Mix dry ingredients, except sesame seeds, in large bowl. Add oil to dry ingredients then slowly add warm water until a ball forms and dough does not stick to the surface. Knead briefly, cover with plastic and let rest for at least 30 minutes. Divide dough into 10 pieces.
Roll out dough with floured rolling pin to about 7 or 8 inches or use tortilla press. Be sure to use waxed paper or parchment paper to prevent the dough from sticking to the press. Put the sesame seeds on a plate and lay the tortilla on the seeds - you can place sesame seeds on one or both sides depending on amount of sesame taste desired. Since the seeds will be cooked directly, a lot of sesame flavor will be released.
Cook each tortilla on non-greased non-stick griddle until each side begins to brown, about 45 seconds to 1 minute per side. Some of the seeds will pop. These tortillas are best served immediately while warm. Keep them covered with a tea towel. If stored, wrap tightly and reheat before serving.
Place tortillas on a platter, add grilled, sliced chicken and top with mango chutney. Garnish with cilantro sprigs, if desired.