Ham and Cheese Soup

Make this tonight. You'll thank me. Then curse me in the morning when you step on the scale.

2 Cups diced potatoes
1 Cup chopped onion
1 Cup grated or chopped carrot
1 Cup chopped celery
2 cans chicken broth
1/2 Cup butter
2/3 Cup flour
1 quart half & half (or 1 qt milk with 3Tbs butter)
1 lb Velveeta, cubed
2 Cups diced ham

Boil veggies in the broth until almost tender. Melt butter and add flour. Put 1/2 of half and half in soup, then add melted butter and flour. Stir or whisk until dissolved. Add rest of half and half. Heat until thick. Add cheese and let melt into soup. Add ham. DO NOT LET BOIL!