DIY Smash Cake for beginner diary free/egg free recipe included

So for my son's 1st Birthday Candy Land Theme I was looking for a Smash Cake Butter Cream Icing I love this link because you can adjust the serving size.  I substituted for soy milk and used I Can't Believe It's Not Butter for all diary ingredients.  I skipped meringue powder because I couldn't find it in the baking aisle.  I probably didn't know what it look like to look for it.  Separate portions out and add food coloring if you like.

  They are so popular for photo op.  I was also looking for a diary free one and couldn't find local bakers to make one for me. I saw this cake on Pinterest.  Of course where else would you find anything your heart desires to make.  I have to say I'm not a baker.  I mess up recipes all the time but this time I solicited the help of my friend in CA.  Boy can she bake you a cake.  Her work is amazing.  She sent me a few online links for tips.  First how to make your own buttercream frosting because the can frosting will not hold the shape it's too soft to decorate on.
This is how to frost the cake to make it flawless.  This gives it the look of fondant but taste so yummy.   You can just bake a cake out of the box and it'll work too even though they are softer.  However for a diary free and egg free my friend gave me this recipe.

 It's called Crazy Mixed Up Chocolate Cake:  3 cups unsifted all purpose flour, 1/2 cup of unsweetened cocoa, not Dutch process (whatever that means), 1 teaspoon salt, 2 cups sugar, 2 teaspoons baking soda, 2 tablespoons of white or cider vinegar (that's right vinegar!), 2 teaspoon of vanilla extract, 2/3 cup of vegetable oil, 2 cups of lukewarm water.  Pre-heat oven at 350 degrees.  place a sifter over a bowl and sift all your dry ingredients together then add in all your other ingredients and mix.  Or you can do what I did and that was to just mix everything without the sifter because I miss this step.  You can now pour mixture into your baking pan.  Smash Cakes are normally about 6" so get two of those.  I wrapped the pan with these Wilton Bake Even Strips soaked with water so that the cake will have a more flat top.
For the decoration I just use candies.  I made the lollipop with twister string in red and green color.  For the ice cream topping.  I just used extra pieces of cake and rolled it into a ball.  Frosted it with icing and tripped some melted chocolate chips.