Line a baking sheet with parchment paper or wax paper. Measure out the oats and freeze the chocolate chips beforehand to prevent them from melting too quickly.

In a medium saucepan, combine sugar, butter, a dash of salt, and evaporated milk. Stirring frequently, bring to a full rolling boil over medium heat. Boil for 30 seconds. A full rolling boil is a vigorous bubbling boil that doesn't stop when stirred.

Remove the saucepan from heat and add oats and dry pudding mix. Stir and let it sit for a few minutes to cool slightly. This resting period is important to avoid cooking the oats.

Add the frozen chocolate chips and toffee chips to the cookie mixture. Gently and quickly stir to incorporate, being careful not to overmix to prevent the chocolate chips from melting completely.

Scoop the cookie dough and drop onto the prepared parchment paper. Sprinkle a bit of sea salt over the cookies before they cool. Coarse sea salt works well for this added flavor.

Allow the cookies to sit for at least 15-30 minutes to set. This is a crucial step for achieving the right texture.