In an Instant Pot combine the beef broth, beer, and apple cider vinegar. Add in the bay leaf. Set the trivet (the metal wire insert), in the Instant Pot, and put the corned beef brisket on it. 1 cup low sodium beef broth, 12 ounces dark Irish beer, 2 tablespoons apple cider vinegar, 1 bay leaf, 3 pounds corned beef brisket
In a small bowl, combine the brown sugar, allspice, ground mustard, dill weed, kosher salt, and black pepper. Sprinkle over the corned beef. Add the minced garlic cloves on top.
2 tablespoons brown sugar, 1 teaspoon dried dill weed, 1 teaspoon allspice, 1 teaspoon ground mustard, 1 teaspoon kosher salt, 1/2 teaspoon black pepper, 3 garlic cloves
Put the top on and seal. Set it to manual, high pressure, 60 minutes. Make sure the valve is set to sealed before you start. After a moment the Instant Pot will beep and say "On." At that point it will start building pressure and eventually the pressure valve will raise and then it will start counting down the 60 minutes. (Please note that you will need roughly 20 minutes for every pound of corned beef you have.)
Once the Instant Pot has counted down the 60 minutes, use a manual pressure release, turning it to venting. Once the valve has fallen you can remove the top. From the time you close the pot to the time you open it will be almost 1 hour and 30 minutes.
Remove the corned beef from the Instant Pot. Tent it loosely and let it rest for 15 minutes.