Please choose the correct ending to complete the given sentence: Food and Entertaining: [header] How to make sugar cookie rice krispie treats [title] Melt the butter in a large saucepan. [step] Over a low heat setting, melt the butter to where it is nearly all liquid. [title] Add the marshmallows.

Ending1: [step] Use a candy thermometer to carefully mix the butter and marshmallows together. You can always stir later if you want an even richer version of the rice krispie treats. Ending2: [step] Pour the butter into the saucepan, one drop at a time. [title] Heat on low until the marshmallows melt and the moisture from the butter is evaporated. Ending3: [step] Stir constantly with a whisk or spoon every 30 seconds for about three minutes until the marshmallows are a light golden colour. Continue whisking every hour or so until melted. Ending4: [step] Combine and stir the butter and marshmallows until everything is melted thoroughly. Remove the pan from the heat and add the sugar cookie mix and salt.

Answer format: ending1/ending2/ending3/ending4