I prepare the mashed potatoes in the morning and set aside in the fridge until a few hours before dinner.
On stovetop add chopped potatoes and pinch of salt to large pot of water, bring to boil and cook until tender.
While potatoes are cooking, add onion and bacon to frypan and cook on high heat for 5-10mins until onion softened and bacon browned. Set aside.
Drain potatoes and add milk and butter and mash/whip until smooth.
Add bacon and cheese to mashed potato. Add in garlic powder and chives and mix to combine. Cover and place in fridge until cooking time.
Spray slow cooker bowl with non stick spray (or you may prefer to line with baking paper)
To the mashed potato, stir in 1 cup of cheese. Reserve 1/2 cup for later.Stir in the green onions - but reserve 1-2 tbsp for later.
Add mashed potato mix to slow cooker and cook on low for 2hrs or until piping hot throughout. Cook with Tea Towel Trick.In final 15mins of cooking time I scatter top of the bake with the remaining cheese to melt and green onions to garnish.
Serve immediately as a tasty side dish. We served ours with BBQ steaks and steamed broccoli, peas and beans.