Press Saute on Instant Pot and heat for 1 minute.
Add chopped bacon and cook 6-8 minutes until crispy, stirring occasionally.
Remove bacon to paper towels to drain.
Discard all but 1 Tbsp bacon fat from pot.
Add chopped onion, carrots, and celery to remaining fat.
Cook 3-4 minutes until onion softens.
Add minced garlic and cook 1-2 minutes until fragrant.
Add salt, smoked paprika, black pepper, coriander, and chili powder to vegetables.
Stir to coat, then add tomato paste.
Cook tomato paste 1-2 minutes, stirring occasionally.
Pour in 1/2 cup beef broth and scrape up browned bits from pot bottom.
Add remaining beef broth, water, diced tomatoes, lentils, and half the cooked bacon.
Stir everything together.
Press Keep Warm/Cancel to turn off Saute.
Close and lock lid with pressure valve set to sealing.
Press Pressure Cook and set time to 15 minutes.
Wait 10-15 minutes for pot to pressurize.
After 15 minutes cooking, let pressure release naturally for 10 minutes.
Switch valve to venting to release remaining pressure.
Serve in bowls topped with reserved crispy bacon.