Preheat your grill to medium. I tend to preheat on high, but these I went right to medium heat. You don't want to burn expensive beef.
Cut your beef into cubes, about 1 to 1 1/2 inch in size.
Cut your veggies into chunky pieces.
Thread your meat and veggies onto skewers, leaving small gaps between.
Season with salt and pepper, I usually leave the pepper until after I grill. I find it burns easily. So it's usually my last step. This is just a personal thing. You do your thing your way.
Brush on the sauce before if you like it cooked into the meat, after if you don't like it cooked into the meat.I like the char and flavour of meat with sauce cooked into it.
Place over direct medium heat on grill and cook each side for about 3 to 4 minutes. This will give you a medium rare kebab.
If you want rare minus a minute off each side.
If you want well done add a minute to each side.
Sprinkle on pepper now if you waited to add it.
Remove from the grill and allow to stand for about 5 to 10 minutes.
Serve with a big old tenderloin loving smile!