I can't figure out where I went wrong here! I attempted to make a meyer lemon tart—I am relatively good around the kitchen, and have made this before with great success. The one real difference was that I used Kerrygold Irish Butter (in a big block) instead of a normal store brand stick butter. (I wanted it to be extra good ;( ) I got thrown off by the butter being in 1 big block despite the measurements, but used a small scale to measure the Kerrygold vs. a stick butter to ensure the quantity was the same. I measured the butter for the crust the same way. I must have messed up somewhere because after I put the curd in the tart, and checked on it in 15 min as the recipe stated, and it looked as if the curd had separated, it puffed up like a soufflé, was spilling over the side! I was careful to incorporate the butter a little at a time, and it looked silky and smooth before being poured into the shell. Did I whisk a little too vigorously? Did I for sure screw up the butter? I suppose it's possible I hit a different unit of measure on my scale. I tried to scrape all the curd out of it's shell to taste the crust and see if it tasted overly buttery, but it's hard to tell now that so much curd has soaked into it :( This is certainly my most epic fail in my 29 years of cooking/baking. Help! I need to understand what happened here... and thank you!