Preheat oven to 350°F. Line two baking sheets with parchment paper.
Whisk flour, baking soda, salt, and cinnamon in a medium bowl; set aside.
Beat softened butter, brown sugar, and granulated sugar until light and fluffy, 2–3 minutes.
Add eggs and vanilla; beat until smooth and creamy.
Mix in dry ingredients on low just until the flour disappears; do not overwork.
Fold in oats, cranberries, pecans, and orange zest if using.
Chill the dough 15 minutes to help control spread (optional but helpful).
Scoop 1½-tablespoon portions onto sheets, spacing about 2 inches apart.
Bake 11–13 minutes, until edges are set and centers still look soft.
Cool on the sheet 5 minutes, then move to a rack to finish cooling.