https://byo.com/article/hoppy-sour-beers/

For water, add calcium chloride to reach about 100-150 ppm chloride. Don't use gypsum or epsom salt because the sulfate will accentuate the bitterness.

Mash at 150 °F (66 °C). Collect wort and boil for 60 minutes, do not add any hops. Cool the wort to 100 °F (38 °C) and transfer wort to a fermenter or keep in pot. Pitch the Lactobacillus of your choice, and add lactic acid as needed to achieve a pH of 4.4. If you are in a rush, sour as warm as you can reliably hold (up to 115 °F/46 °C), ideally above 80 °F (27 °C). Approximate souring time 1–3 days to reach pH 3.3–3.4. You can measure by taste, but the sweetness of the wort can make acidity seem milder than it will post-fermentation (even though the pH will rise slightly with fermentation and dry hopping). Once the desired acidity is achieved, return the wort to the kettle and heat to 180 °F (82 °C). Once the temperature is reached, turn off the heat and add the hops. Allow them to steep for 20–30 minutes before chilling to 70 °F (21 °C). Aerate and pitch a large starter of Brett (most commercial Brett strains are not packaged at a high enough cell-count to pitch directly). A 3-L starter on a stir-plate for a week should be adequate. Once the gravity stabilizes (two to four weeks), the beer is ready to package. If you are bottling, add the dry hops to the primary fermenter. If kegging, bag and weight the hops (I use new nylon knee highs and glass marbles) adding them directly to the keg during natural conditioning. Aim for 2.7 volumes of CO2.