Preheat the oven to 350°F (175°C). Line a baking sheet with parchment paper or a silicone baking mat.
In a large mixing bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy. This can be done with a hand mixer or stand mixer.
Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
In a separate bowl, whisk together the flour, baking soda, and salt. Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Fold in the oats, chocolate chips, crushed pretzels, shredded coconut, and chopped nuts (if using). Stir until all ingredients are evenly distributed throughout the dough.
Drop rounded tablespoonfuls of dough onto the prepared baking sheet, spacing them about 2 inches apart.
Bake for 10-12 minutes, or until the edges are lightly golden. The cookies will still be soft in the centre but will firm up as they cool.
Allow the cookies to cool on the baking sheet for 5 minutes, then transfer them to a wire rack to cool completely.