To prepare cake, preheat oven to 350F. Grease and line an 8-inch square cake pan.
In a large bowl, sift flour, baking powder, baking soda and salt. Mix well.
In the bowl of an electric mixer fitted with the paddle attachment, mix eggs and sugar until well combined. Gradually add oil and 1 teaspoon of vanilla, mix until just blended.
With the mixer on low, slowly add half the flour mixture; mix until just blended. Add the buttermilk, mix until just blended. Slowly add remaining flour mixture, scraping down sides of the bowl with a spatula, as necessary, until just blended.
Pour batter into the prepared pan. Transfer pan to oven and bake for 18 to 20 minutes. Let cake cool in pan for 15 minutes. Then invert it onto a greased rack. Let cool completely.
To prepare buttercream, beat butter for a few minutes in a standing mixer with the paddle attachment on medium speed. Add powdered sugar and turn your mixer on low, beat until the sugar incorporates with the butter. Add 1 teaspoon of vanilla and heavy cream, beat on medium speed for another 3 minutes, or until buttercream becomes light and fluffy.
To assemble cake pops, prepare two cookie sheets lined with parchment paper.
Break the cooled cake into a few big trunks by hand, place them into the bowl of an electric mixer fitted with the paddle attachment and mix on medium speed until the big pieces turn into crumbs.
Add frosting gradually into the cake crumbs and blend until the mixture becomes a dough, about 1 to 1 1/2 cups of frosting.
Scoop dough into 10 to 20 teaspoon-sized balls for the heads, and 10 to 20 tablespoon-sized balls for the bodies. Place them on the prepared cookie sheets. Refrigerate for 30 minutes.
Remove the small cake balls from the refrigerator. Melt white candy melts in the microwave gradually, 10 second intervals and stirring in-between. Dip one end of a lollipop stick in the candy melts and insert all the way through a small cake ball, leaving about one centimetre of the stick at the bottom. Repeat with all the small cake balls. Set aside for 30 seconds.
Remove the large cake balls from the refrigerator.
Dip each small cake ball in the white candy melts and gently tap off excess. Carefully but quickly insert the end of the stick into a large cake ball. Secure the head and body part and let it stand for 30 seconds. Repeat with the remaining cake balls.
Dip each snowman body in the white candy melts and gently tap off excess. Place cake pop onto a piece of parchment paper. Let it dry completely.
Place the red candy melts in a microwavable Ziploc bag. Microwave on high for 20 to 30 seconds to completely melt the candy melts. Push the melted candy toward one corner of the bag. With a pair of scissors, snip off a very small opening, and start piping the hat and scarf on each snowman cake pop.
Repeat with the black candy melts for the eyes, mouths, and bottons.
Repeat with the orange candy melts for noses.