Mince 1 tsp. fresh rosemary and set aside. In a small sauce pan, add 8 oz. concord grapes, 1 tbsp. honey, and 1 tbsp. balsamic vinegar.
Use a potato masher or fork to break up grapes in the sauce pan. Turn heat to MEDUIM-HIGH, and allow to boil and reduce for 7 minutes, stirring occasionally.
After 7 minutes, reduce heat to MEDIUM, add 1 tsp. of minced rosemary and ½ tsp. honey mustard. Stir, and allow to further reduce for 2 more minutes. Remove from heat.
Carefully push sauce through a mesh strainer, leaving only seeds, skins and rosemary. Place sauce in a sealed container until ready to assemble appetizers.
Preheat oven to 350 F. (175 C.) and thinly slice baguette into 18 pieces. Place slices on a baking sheet with a rack. When ready, place baguette slices in oven and toast for 7-10 minutes.
Use a paper towel to thoroughly dry both sides of ½ pound skirt steak. In a small bowl, mix 1 tsp. kosher salt, 1 tsp. fresh pepper, ½ tsp. onion powder and a pinch of cardamom. Thoroughly rub both sides of steak with spice mixture.
Turn heat to HIGH under a sauté pan, and allow it to heat for 1 minute. Add 1 tbsp. olive oil to the pan and then the seasoned skirt steak. Allow it to sear for 3 minutes maximum - not a moment longer. Flip, and sear for just 2 minutes on the other side. Remove and allow it to rest under tin foil for 10 minutes. Then, slice into 18 pieces.
Apply a liberal amount of Florette cheese to each slice of baguette, add a slice of skirt steak, liberally swipe each piece of skirt stake with balsamic-grape reduction, top with champagne grapes and a single leaf of arugula.