This was one of the first wedding cakes I did and I was nervous! I loved the square tiers and the rhinestone ribbon was just fabulous. I love the look of smooth fondant but I don’t love the taste, and people usually prefer the smooth frosting option.
To get smooth and even frosting I give my cake a crumb coat then put it in the refrigerator to chill. Once it is chilled I fill a large zip lock bag (a frosting bag works of course but I found I had to refill it too fast) and cut a 1/2 inch corner off one side. I then just pipe stripes top to bottom all around the cake (right next to each other no space between!) Let it sit for 5 minutes, the coolness of the cake helps the frosting to firm just a little.
Then I use this Nordic Ware Stainless Steel Blue Handled Baker’s Blade Dough Cutter to just go around without too much pressure, holding the dough cutter sideways and smooth the stripes, you will have a little excess frosting as you go, just wipe it clean and go back. It is amazing how well it works! Of course it takes a bit of practice and I always go back over with my spatula (I LOVE this one, use it for everything Wilton 9 Inch Angled Spatula, With Black Handle) to fill in any little holes.
IMPORTANT, when smoothing always make sure you start each stroke with a CLEAN tool, frosting tends to harden and will scratch your smooth cake. To smooth the top pipe lines across and them smooth them in one direction. Use the small spatula to round up the sides and over the top to finish it off.