Peel and chop potatoes into 1" cubes. Put in a pot and fill with water, just an inch over the potatoes. Cook until fork tender, about 10 minutes. Drain and set aside.
Add oil and garlic, celery and carrots and cook for about 5-8 minutes, just as the veggies start to soften. Add flour and cook an additional 2 minutes, stirring often.
Slowly add chicken broth to garlic and cook over medium heat, stirring constantly, until mixture is thickened and bubbly. Stir in cooked potatoes, skim milk, Italian seasoning, and salt and pepper to taste. Reduce heat to simmer and cook for 10 additional minutes.
Remove from heat. Add the cheddar cheese and stir until melted. Use a potato masher to mash some of the potatoes, but not all so it's still creamy and chunky.
Note: garnish with bacon bits or fresh parsley if desired.
There are 274 calories in 1 serving of Potato Soup.