Plump the raisins. Place raisins in a bowl and cover with the hot water. Let them sit for 10–15 minutes. Drain well and pat dry with paper towels. Set aside.

Prep the oven and pans. Heat the oven to 350°F (175°C). Line two baking sheets with parchment paper.

Cream the butter and sugars. In a large bowl, beat the butter, brown sugar, and granulated sugar until light and creamy, about 2–3 minutes. Scrape down the bowl as needed.

Add eggs and vanilla. Mix in the eggs one at a time, then add the vanilla and beat until smooth.

Whisk dry ingredients. In a separate bowl, whisk together flour, baking soda, baking powder, cinnamon, and salt.

Combine wet and dry. Add the dry ingredients to the butter mixture and mix on low just until combined. Do not overmix.

Stir in oats and raisins. Fold in the oats, then the drained raisins and nuts if using. The dough will be thick.

Rest the dough. Let the dough sit for 15 minutes. This helps the oats hydrate and keeps the cookies chewy.

Scoop. Use a 2-tablespoon scoop (about golf-ball size) to portion dough onto prepared sheets, leaving 2 inches between cookies. Gently flatten the tops just a bit with your fingers.

Bake. Bake 10–12 minutes, until edges are set and lightly golden but centers still look slightly soft. Rotate pans halfway through for even baking.

Cool. Let cookies cool on the sheet for 5 minutes, then transfer to a rack to cool completely. They’ll set up as they cool.