Arrange saltines salt side down on the parchment, with no room between them.
Combine butter and sugar in a saucepan over medium heat, whisking frequently until sugar dissolves.
Bring to a boil, then boil for 3 minutes without stirring, until dark caramel-colored.
Pour toffee mixture over the saltines and spread evenly.
Bake for 8 minutes, until bubbly.
While saltine toffee is baking, carefully chop Cadbury mini eggs. (See expert tips for advice!)
Immediately upon removing saltine toffee from oven, scatter chocolate chips on top. Wait 2 minutes, then spread the melting chips to create a chocolate layer over the toffee.
Sprinkle with chopped mini eggs.
Wait until the baking sheet is cool enough to handle, then put in the refrigerator for 2 hours.
Remove from the refrigerator and break into pieces, peeling off the parchment paper.
Notes
Note that the Nutrition Facts information for this dessert is just a guide, since Cadbury Mini Eggs are not an ingredient in the database! I used M&Ms as a substitute.
Expert Tips:
To chop the mini eggs, I find it it best to hold the handle of the knife very close to the blade, just above the mini egg. Chop just one at a time at first, until you get the hang of it. If you want to chop the mini eggs more finely, that is easy to do once you have cut them each in half. An alternative is to put the mini eggs in a sturdy freezer bag and tap them with a mallet. The chopped mini eggs will look a little messier though.
Try not to stir the caramel while it is boiling. Not stirring will help it set properly.
Using a small offset spatula is the best way to spread the caramel and the melted chocolate chips.
Work quickly after baking. The chocolate needs to hit the toffee when it is quite hot so that the chips will melt completely.
If your butter/sugar mixture is separating, try warming the butter to room temperature before combining with the sugar.
Storage Tips: Store in an airtight container in the refrigerator for up to a week. You can also freeze this toffee for up to 2 months.