Line 8x8 or 9x9 pan with parchment paper or foil. Grease with butter.
1 Tbsp Butter
In deep pan, melt butter over low heat. Add brown sugar, half-and-half, and corn syrup. Mix well.
1 cup butter, 16 oz brown sugar, 2 cups half-and-half, 1 cup light corn syrup
Cook and stir over medium-high heat till mixture boils.
Clip candy thermometer onto pan and reduce heat to medium. Continue boiling till caramel reaches the temp you are looking for. It will take apx 45m to reach 248°). Occasionally stir caramel to avoid burning.
Remove caramel from heat and stir in vanilla. Pour mixture into pan to cool and then cut as desired to make old fashioned caramels.
1 tsp vanilla
Notes
To cook faster, swap the half-and-half for 14oz sweetened condensed milk. This will reduce cook time to apx 20m.I normally double this recipe, I use a 9x13 pan to cool the caramel.