In a small bowl, whisk together the vegetable oil (or melted butter), ranch seasoning mix, dried dill weed, lemon pepper, and garlic powder.
Place the oyster crackers in a large mixing bowl and pour the seasoning mixture over them. Toss gently to coat evenly.
Spread the coated crackers in a single layer on an ungreased baking sheet.
Bake for 15 to 20 minutes, stirring gently halfway through to ensure even crisping.
Remove from the oven and let cool for 10 minutes before serving or storing.
Notes
For a spicier version, add 1/2 teaspoon of red pepper flakes or a pinch of cayenne pepper. Store in an airtight container at room temperature for up to a week.