Preheat Oven:

• Preheat your oven to 250°F (120°C). Line a large baking sheet with parchment paper or a silicone baking mat for easy cleanup.

Prepare the Snack Mix:

• In a large mixing bowl, combine the Chex cereal, Saltine minis, nuts, and pretzels. Stir gently to mix all the ingredients evenly.

Make the Toffee Coating:

• In a medium saucepan, melt the butter over medium heat. Add the dark brown sugar, corn syrup, and kosher salt. Stir constantly until the mixture begins to boil. Let it boil for 3-4 minutes without stirring, allowing the sugar to fully dissolve and the mixture to thicken.

Add Vanilla and Baking Soda:

• Remove the saucepan from heat and stir in the vanilla extract and baking soda. Be careful, as the mixture will bubble up.

Coat the Snack Mix:

• Immediately pour the toffee mixture over the Chex mix, using a spatula to gently toss and coat all the ingredients. Ensure that everything is evenly coated with the toffee mixture.

Bake the Chex Mix:

• Spread the coated snack mix in an even layer on the prepared baking sheet. Bake in the preheated oven for 45 minutes, stirring every 15 minutes to ensure even coating and to prevent burning.

Cool and Serve:

• Once done, remove from the oven and let the Chex mix cool completely on the baking sheet. Once cooled, break it into pieces and store in an airtight container.