Place an oven rack in the middle position. Preheat the oven to 350 degrees F.
Line 2 baking sheets with parchment paper or a silicone mat and set aside.
Place another baking sheet, plate or airtight container in the freezer.
In a large bowl, whisk together the almond butter, brown sugar, coconut oil, granulated sugar vanilla, cinnamon and salt in until creamy, about 30 seconds. Add the eggs one at a time, whisking well after each addition. Add the oats and baking soda and mix to combine. Add the popcorn, chocolate-covered raisins, nonpareils and candy-coated chocolates. Using a rubber spatula, gently fold in until evenly incorporated.
Scoop 1/4-cup-sized balls of dough (about the size of a plum) onto the baking sheets 2 inches apart (see Cook's Note). Dot each cookie with a few pieces of popcorn and candy. Sprinkle each with a pinch of flaky salt, if desired. Bake until lightly browned and just set in the center, begin checking for doneness at 14 minutes. These cookies have a tendency to spread into uneven blob shapes in the oven, so I like to shape them back into circles as soon as they come out of the oven using an inverted bowl on top of the cookies to gently curve the edges back into alignment. Let cool on the pan completely (well, enjoy one or two while they’re still warm but then let the rest cool on the pan).
While the cookies cool, remove the ice cream from the freezer to slightly soften. Scoop 1/3 cup of ice cream onto the flat, bottom side of half the cookies. Top with another cookie and gently press down to flatten. Place the ice cream sandwich in the freezer on the cold baking sheet, plate or container. Repeat with the remaining cookies and ice cream.
Keep frozen until ready to enjoy!
Using an ice cream scoop or something that allows you to press the cookie dough mixture together helps when portioning because the raw cookie dough can fall apart easily.