Spicy Bean-Less Chili

I found this recipe online while looking for a bean-less chili recipe to try. Alex loved it, but in following the recipe, spice-wise, I found it way too spicy for my tastes. I will definitely be doing it again, but will lessen the amount of spices. I'll give you the original recipe and then say the things I did differently (I did modify it slightly).

1 lb lean ground beef
1 cup diced celery
1 can crushed tomatoes (28 oz)
1 small can diced green chilies
1/4 cup chopped raw onion
1/2 teaspoon salt
1 teaspoon cayenne pepper
3 teaspoons ground cumin
6 teaspoons chili powder

Brown ground beef and drain.
Add all ingredients to crock pot and stir. Set on high for 2 hours or low for 4 hours.

What I did differently: I left out the celery, green chilies and salt. I used one onion (didn't measure it so it was likely more than what the recipe calls for). I added about a half cup of chopped green pepper and 4 diced mushrooms. I followed the spice instructions exactly, but next time I'm planning on using 1/2 teaspoon cayenne pepper, 1 teaspoon of cumin and 3 teaspoons of chili powder, then adding more chili powder if needed. I cooked it on low for 5 hours before I had any of it. Alex pointed out this evening that it was less spicy today after it had sat overnight.