Crazed Culinarian

Riddle: You were once a judge in a chocolate eclair-making contest, and you awarded the blue ribbon for first place to an outstanding chef by the name of Vera Good. However, another disgruntled chef who lost the competition, whose name was Notu Swell, experienced a mental meltdown and a subsequent nervous breakdown over the loss. He vowed to seek revenge against you, blaming you entirely for his not winning. With the cunning of a serial killer, he was able to entrap you and imprison you in the basement of his house. Once he had you in his clutches, he approached you and revealed his evil plan: "You see before you, five chocolate eclairs which I just finished baking. I have piped a deadly poison into four of these, but the fifth one is poison-free. You must choose one of the five eclairs, based on the matching recipes I have handed you, and eat the eclair which you believe not to be the poisoned one. If you can identify The Only Chocolate Eclair Recipe Which Has No False Ingredient In It, then you may eat it safely, and I will then release you. However, I doubt you have the knowledge to properly judge which eclair recipe is the true one. At any rate, you must eat one of my pastries, if you ever again wish to see the light of day." These are the five recipes from which you must choose. Your very life depends on it: RECIPE #1: 2 tbsp unsalted butter; 1/2 tsp salt; chocolate pastry cream; 1/2 cup whipping cream; 4 large eggs; 8 oz. semi-sweet chocolate; 1 oz. freshly ground paprika; 1 tbsp white sugar; 1 cup flour; 1 cup water. RECIPE #2: 2 tbsp unsalted butter; 1/2 tsp kosher salt; 2 oz. distilled white vinegar; vanilla pastry cream; 2 cups whole milk; 4 eggs; 1/2 cup confectioner's sugar; 1 cup flour; 1 tsp vanilla extract. RECIPE #3: 2 tbsp unsalted butter; 1/2 tsp salt; chocolate pastry cream; 1/2 cup whipping cream; 4 large eggs; 1/4 cup chopped oregano; 8 oz. semi-sweet chocolate; 2 tbsp corn syrup; 1 cup flour; 1 cup water. RECIPE #4: 2 tbsp unsalted butter; 1/2 tsp salt; vanilla pastry cream; 1 cup whipping cream; 4 large eggs; 8 oz. semi-sweet chocolate; 1 tbsp white sugar; 1 cup flour; 2 tbsp corn syrup; 1 cup water. RECIPE #5: 2 tbsp unsalted butter; 1/2 tsp kosher salt; vanilla pastry cream; 2 cups of whole or 2% milk; 1/2 cup whipping cream; 2 cups finely chopped onion; 1/2 cup confectioner's sugar; 4 large eggs; 8 oz. semi-sweet chocolate; 1 tsp vanilla extract; 1 tbsp white sugar; 1 cup flour. "Now, which of the five recipes is the ONLY one which contains no poison --- THE ONLY ONE HAVING NO FALSE ECLAIR INGREDIENT?" Which one will you choose?