Preheat the oven to 395°F. Line 6 jumbo muffin tins with jumbo parchment muffin liners.
In a large mixing bowl, combine the melted butter and sugar. Stir until creamy. Add the eggs and stir until combined.
Add the cassava flour, baking powder, baking soda, sea salt, and yogurt. Stir until the batter is smooth. Fold in the chocolate chunks.
Divide the batter between the 6 jumbo muffin tins. The muffin tins will be heaping.
Bake for 30-35 minutes. The muffins should be browned and bounce back when gently pressed. Let the muffins cool for 5-10 minutes in the muffin pan before transferring them to a cooling rack to cool completely.
Store the muffins in an airtight container at room temperature, in the fridge, or in the freezer.
Notes
If using berries instead of chocolate chips, omit the additional 3 T. of coconut yogurt and extend the bake time by 5-10 minutes.