Step 3: Prepare the vegetables. Peel and cut the onion into large chunks. Peel the carrots and remove the ends. Slice the carrots and celery into thick long sticks. Smash garlic cloves with the flat side of a knife and peel away the skins.
Cook Pot Roast
Step 1: After an hour, use paper towels to pat the beef dry on all sides (this helps the meat brown), and then rub the beef on all sides with the spice mixture. The beef should be well seasoned on all sides with the spices.
Step 2: Add oil to the bottom of a 6-quart Instant Pot (or electric pressure cooker). Select the “Sauté” setting and choose high heat. When the oil is hot and shimmering, add the beef. Cook until well-browned on all sides, about four minutes per side. Transfer the browned beef to a plate.
Step 3: Add the onion, carrots, celery, and garlic cloves to the pot and cook, stirring occasionally until they start to sweat and lightly brown around the edges, about 6 minutes. Transfer the vegetables to a plate.
