Preheat the oven to 200°C/ Gas 6. For the butterscotch-bacon brittle, spread the bacon on a lined baking sheet. In a medium saucepan, bring the butter and sugar to a boil, stirring and watching constantly as soon as you see the sugar melting.
Boil for about 3 minutes, then carefully pour the toffee mixture evenly over the bacon. Bake in the preheated oven for about 4-5 minutes.
Remove from the oven and while the toffee is still really hot, sprinkle the butterscotch chips over the top so they melt onto the toffee. Let cool completely before breaking the bacon into pieces. Set aside.
To make the cinnamon rolls, in a large bowl dissolve the yeast in the warm milk. Add the sugar, butter, salt, eggs and flour, and mix well to combine. Turn the dough out onto a lightly floured surface and knead for 5–10 minutes.
Bring it together into a large ball, then place in a bowl, cover and let rise in a warm place for about 1 hour or until the dough has doubled in size.
Roll the dough out on a lightly floured surface, until it is approximately 54 x 40 cm and 1 cm thick. Preheat the oven to 200°C (400°F) Gas 6.
To make the filling, combine the brown sugar and cinnamon in a bowl. Add the butterscotch-bacon brittle. Spread the softened butter over the surface of the dough, then sprinkle the filling mixture evenly over the surface.
Working carefully, from the long edge, roll the dough down to the bottom edge. Cut the dough into 4.5cm slices. Place the slices in a lightly greased baking pan and bake in the preheated oven for 10-12 minutes or until light golden brown.
Let cool in the pan. Meanwhile, combine all the icing ingredients in a large bowl and beat on high speed with an electric mixer until thoroughly combined. Spread the cooled rolls generously with the icing and serve.