Slow Cooker Bombay Potatoes

I was inspired to make these because of a ready-made package I bought last week and microwaved. As would be expected, even more delicious when made from scratch. And very easy, to boot. It involves garam masala, which is just a combination of spices. Interestingly, this is something that may vary according to region or personal taste and may even include wet ingredients. I include this basic combination of spices that worked for me:

1 Tbsp. cumin
1 1/2 tsp. ground coriander
1 1/2 tsp. ground cardamon (another call for cardamon, yea!)
1 1/2 tsp. ground pepper
1 tsp. cinnamon
1/2 tsp. ground cloves
1/2 tsp. ground nutmeg

Now for the potato recipe itself:

1 medium onion, chopped
3 lbs. potatoes, peeled and cubed (or not peeled, if you're like me. I used small, Yukon Gold
  potatoes, whose skins were very thin).
1 can diced tomatoes (Scottish translation = 1 tin of diced tomaities) or 3 fresh, chopped.
2 tsp mustard seeds
1 tsp ground ginger
1 tsp garam masala
1 1/2 tsp turmeric
1/2 tsp ground cumin
1/2 tsp chili powder
1/4 tsp dried chili flakes
3 tbsp olive oil
1 1/2 to 2 tsp kosher salt
freshly cracked black pepper

Heat the oil and add the mustard seeds. 

As soon as they begin to pop, add the onion and cook until translucent. 

Add spice mix and cook for another 3 minutes to get the flavors going. 

Throw in chopped potatoes and stir until all are covered in spice.  

Add tomatoes, salt and pepper.

Put in slow cooker on high for about 3 hours.

You can sprinkle with chopped parsley or coriander but, come on, we're Nanners and not into the fancy, just the delicious, which this is.