Place the bread cubes, margarine cubes, pecans, raisins, cinnamon and sugar into the mixing bowl. Mix with the rubber spatula until fully combined.
Lightly coat large cassrole dish with margarine or non-stick spray. Spread bread mixture evenly in casserole dish
Place a piece of parchment paper over the top and then with a piece of aluminum foil.
Let sit for 10 minutes This will allow the bread to soak up the custard mixture.
Place the bread pudding into the 350°F oven and bake for approximately 1 1/2 hours or until the internal temperature reaches 180°F on the probe thermometer inserted into the center
Remove the aluminum foil and parchment paper for the last 30 minutes of the baking time for the top of the bread pudding to brown.
Remove the bread pudding from the oven and cool to room temperature.
Serve with rum sauce and garnish with fresh berries and mint leaves.