1/2 cup unsalted butter (don’t use salted it will splatter like crazy)
1/2 cup light corn syrup
1/2 cup granulated sugar
1/2 cup packed light-brown sugar
1/2 cup sweetened condensed milk
1/8 tsp salt
3/4 tsp vanilla extract
Maldon sea salt or fleur de sel (optional)

Directions
Butter an 8 by 8-inch baking dish. Place butter in a large microwave safe bowl (not anything plastic, something micro safe glass or ceramic), heat in microwave until melted.
To bowl with butter, add corn syrup, granulated sugar, brown sugar, sweetened condensed milk and salt and whisk mixture very well. Return to microwave and cook mixture on HIGH power for 6 to 7 minutes (I recommend taking it out around 6 and testing either with a candy thermometer which should register between 238 – 242 degrees or placing a small spoon of the caramel in a bowl of ice water then remove it from the water and it should have formed a small pliable ball – nothing too soft or too hard. If it needs a little more time return to microwave and heat in 20 second increments. Mine was done at 6 minutes 20 seconds but will will vary slightly based on the wattage of your microwave and the size of the bowl you use).
Using hot pads, carefully remove bowl from microwave. Add in vanilla extract and mix well. Pour mixture into prepared baking dish. Sprinkle top lightly with Maldon sea salt or fleur de sel. Place in refrigerator until set, about 20 – 30 minutes. Cut into rectangular pieces (I cut into rows slightly less than 1/2-inch then cut each row into three) and wrap in cut rectangles of wax paper.