Heat oven to 350°F; line two baking sheets with parchment.
Cream butter and both sugars in a large bowl 2-3 minutes until light and fluffy. Beat in egg and vanilla.
Whisk flour, baking soda, and salt separately; gradually mix into butter just until combined.
Fold in chips and cranberries evenly.
Drop rounded tablespoons of dough about 2 inches apart on sheets. Press down slightly; cookies spread little.
Bake 10-12 minutes until edges set and start turning golden; centers should look slightly underbaked for soft cookies.
Cool on sheet 5 minutes; transfer to rack to cool completely. Store airtight up to 5 days.