Melt bacon grease (or butter) over medium-high heat in a large dutch oven or stock pot.
Add onion and garlic, stirring occasionally until softened, 5-6 minutes.
Add flour, salt, pepper, and 1 tsp Italian seasoning. Combine well with a whisk to form a roux for the chowder. Stir frequently and allow to lightly brown, 3-4 minutes.
Add chicken stock slowly, 1 cup at a time, whisking until the mixture thickens. Once thickened, add cream of chicken, milk, cream cheese and remaining seasonings. Whisk until the cream cheese is fully melted and incorporated. Bring to a boil, whisking frequently to ensure the sauce doesn't burn.
Add ham, potatoes o'brien, and the peas and carrots and simmer 10-15 minutes or until everything is fully heated through. Add cheese and mix well.
Serve hot with any toppings of your choice