Sounds a little weird, but I catered to the Masters golf tournament in Augusta once and everyone there loved it.
- In a large frying pan cook corned beef on med heat to melt the fat off then set aside to cool.
- Once cooled, dice both the bell pepper and the onion and mix into the corned beef with a large wooden spoon.
- Then add the coleslaw mix the same way.
- Then add the horseradish and salt and pepper to taste.
- Finally add in the mayo.
- It's like with chicken or tuna salad, everyone likes a different consistency, so use the mayo to achieve desired viscosity.