Beef Kebobs with Pineapple and Parsley Sauce

For the Parsley Sauce:
3-cups fresh flat-leaf parsley
2-cloves garlic, peeled
2-tbsp red wine vinegar
1-tsp crushed chili flakes
1-tsp sugar
11/2-tsp kosher salt
1/2-tsp freshly ground black pepper
1/2-cup olive oil

For the Beef Kebobs:
1 1/2-lbs top sirloin, cut into 3/4-inch cubes (about 40 cubes)
1-2lb pineapple, cut into 3/4-inch pieces (about 40 pieces)
20-8 inch wooden or bamboo skewers, soaked in water for 30 minutes
Salt and freshly ground black pepper

For the Parsley Sauce:
In food processor bowl, blend together the parsley, garlic, vinegar, chili flakes, sugar, 1 1/2-tsp salt, and 1/2-tsp pepper until smooth
With the machine running, gradually add the olive oil until incorporated
Place half of the mixture in a medium bowl
Place the remaining mixture in a small serving bowl
Cover with plastic wrap and refrigerate until ready to serve

For the Beef Kebobs:
Place the beef in the medium bowl with the parsley sauce
Toss well until the beef is coated with the mixture
Cover and refrigerate for 3 hours

Preheat a gas or charcoal grill
Thread the skewers starting with a piece of pineapple, then a cube of beef
Repeat with another piece of pineapple and another cube of beef
Continue with the remaining skewers
Grill the skewers for 2 to 3 minutes each side (for medium rare) or until desired doneness
Season with salt and pepper
To serve, arrange the kebobs on a serving platter
Drizzle with the remaining reserved parsley sauce or serve the sauce on the side as a condiment