Tame my Tikka!

I am trying to make a quick Chicken Tikka. Not Tikka Masala, just Chicken Tikka. I have tried several pastes and spice mixes I pick up at my local Indopak grocery store. Problem is they are all way, way too spicy, even if I use half of the spice mix they call for. Is there a way to tame down the spiciness of the marinade/spice mix without turning the dish into Tikka Masala? I was hoping to just use a spice paste or mix instead of having to deal with a bunch of different expensive spices I rarely use.