Pat the chicken thighs dry with a paper towel and season both sides with a generous amount of salt and pepper and allow to temper at room temperature while you make the glaze.
In a small sauce pot, combine the blackberries, sugar, lemon juice, and lemon zest. Heat over high heat and once brought to a simmer, reduce heat and just barely simmer for 10 minutes.
Combine cornstarch and water together with a fork until well combined. Slowly whisk the cornstarch/water mixture into the simmering berry glaze and allow to simmer for 1 more minute. Remove from heat and set aside.
Heat a large saute pan (oven proof) over high heat and then add 2 T canola oil. Once the oil is hot, add the 4 chicken thighs and allow to sear for 3 minutes on both sides.
Place the entire pan in the oven and allow to gently cook the chicken the rest of the way for 5 minutes. Remove the thighs from the pan and allow to rest for 5 minutes.
Toss the chicken thighs in the warm blackberry glaze and eat!