Drop the tomatoes into boiling water for 30-40 seconds then immediately submerge in ice water.
Peel, core and dice fresh tomatoes to equal 12 cups.
In a heavy bottomed saucepan, saute the diced onion over medium-high heat in 2 Tbsp of olive oil. Cook for 5-7 minutes until the onion has softened and browned. Add 2 clove minced garlic and continue cooking until fragrant around 1-2 minutes.
Add the diced tomatoes, brown sugar, apple cider vinegar and seasonings to the pot with half of the tomato paste and the lemon juice. [Tip: Reserve the remaining tomato paste to adjust the thickness at the end of cooking]
Simmer over medium-low for 1 1/2 hours or until reduced by half and thickened.
Cover with a lid, but leave off-set to allow the moisture to evaporate. Stir periodically to prevent sticking.
At the end of cooking, test the thickness and add additional tomato paste if desired mixing until the tomato paste is fully dissolved. Adjust the amount according to the juice released by the tomatoes and your preference.
Use an immersion blender or ladle into a stand blender and blend until chunky smooth.
Cool to room temperature, then chill thoroughly for 8 hours or overnight before using.
May be stored chilled in an airtight container for up to week.