What you need
This makes an 8-inch (20 cm) square pan of 16 brownies with a deliberately modest dose.
- For the cannabutter: 1 g of cannabis flower, 1/2 cup (113 g) of unsalted butter and 1/2 cup of water.
- For the brownies: all of the cannabutter, 1 cup (200 g) of sugar, 2 large eggs, 1 teaspoon of vanilla, 1/3 cup (35 g) of cocoa powder, 1/2 cup (65 g) of all-purpose flour, 1/4 teaspoon of salt and 1/4 teaspoon of baking powder.
- Equipment: a baking tray and parchment, a small saucepan, a fine sieve or cheesecloth, an 8-inch pan and, ideally, an oven thermometer.
Step 1: Decarb the flower
Cannabis makes its THC mostly as THCA, an acid form that only converts to THC with heat. In a 2016 lab study in Cannabis and Cannabinoid Research, THCA was essentially gone after 30 minutes at 110°C, while temperatures below 100°C did not finish the job within an hour. An Italian study in Clinical Chemistry and Laboratory Medicine fully decarbed flower in an ordinary static oven at 145°C for 30 minutes and found that pre-heating also raised the final cannabinoid levels in oil.
- Break the flower into small pieces and spread it on a parchment-lined tray.
- Bake at 110°C (230°F) for 30 to 40 minutes, or at 145°C (about 290°F) for 30 minutes, stirring once halfway.
- Let it cool, then grind it coarsely. For more detail, see why and how to decarb weed.
Step 2: Make the cannabutter
The fat does the work here: in the Italian study, oil extracted cannabinoids significantly better than water. For a bigger batch, see how to make cannabis butter.
- Melt the butter with the water in a small saucepan over low heat; the water helps keep the temperature down.
- Stir in the decarbed flower and keep the mixture just below a simmer for about 2 hours, stirring now and then. Do not let it boil hard.
- Strain through a fine sieve or cheesecloth into a container, pressing gently.
- Chill until the butter sets on top, then lift it off and pour away the water.
Step 3: Bake the brownies
Mix thoroughly and cut evenly. Licensed edibles labelled with more than 5 mg of THC must contain between 85% and 115% of the stated amount (Cannabis Regulations), but a home batch gets no such check, so a poorly mixed pan can hide a much stronger square.
- Heat the oven to 175°C (350°F) and line the pan with parchment.
- Melt the cannabutter gently and whisk it with the sugar, then beat in the eggs and vanilla.
- Sift in the cocoa, flour, salt and baking powder and stir until no streaks of flour or butter remain.
- Spread the batter evenly and bake for 20 to 25 minutes, until a toothpick comes out with a few moist crumbs.
- Cool completely, then cut into 16 equal squares, 4 by 4.
How strong is each brownie?
Health Canada warns that there is no convenient way to test homemade cannabis extracts and that they may be extra potent, but you can work out the most THC a batch could hold. Legal flower labels show Total THC in milligrams per gram, which by law already accounts for THCA converting into THC (Cannabis Regulations). Multiply it by the grams of flower, as Health Canada's label guide does for a package, then divide by the number of squares.
- 1 g at 150 mg/g: up to 150 mg in the pan, or about 9 mg per square.
- 1 g at 250 mg/g: up to 250 mg, or about 16 mg per square.
- 3.5 g at 250 mg/g: up to 875 mg, or about 55 mg per square.
What a safe first serving looks like
The real amount can only be lower than the ceiling, but you cannot know by how much, so plan around the ceiling. Health Canada suggests new consumers look for 2.5 mg of THC or less, and a legal edible package may contain no more than 10 mg (Health Canada). If your flower is around 150 mg/g, a quarter of a square is close to that 2.5 mg starting point; with stronger flower, cut smaller pieces. The edibles dosage guide has more examples.
Eating them safely
Per Health Canada, edibles can take 30 minutes to 2 hours to start working and up to 4 hours to reach full effect; effects can last up to 12 hours, with some residual effects up to 24 hours. The body also turns swallowed THC into a stronger compound, 11-hydroxy-THC. Legal edible labels carry the warning that consuming more before you feel an effect can cause cannabis poisoning, including severe anxiety and panic attacks.
- Eat a small piece and wait at least 4 hours before deciding on more.
- Skip alcohol and other drugs; Health Canada says combining them increases impairment and the risk of adverse effects.
- Do not drive.
- Know the warning signs: adverse effects can include a rapid heart rate, dizziness, anxiety, nausea and vomiting, and serious reactions can include psychotic episodes and seizures.
- If you have a health condition, take medication or have questions about cannabis and your health, ask a doctor or pharmacist first.
Storing and labelling
Cannabis brownies look exactly like ordinary brownies. Health Canada advises labelling homemade edibles clearly, storing them separately from regular food, and keeping all cannabis locked away and out of sight and reach of children and pets (Health Canada). It has reported children being hospitalized after eating edibles that looked like ordinary candy or food and were kept in the fridge or freezer without child-resistant packaging (Health Canada advisory). If you suspect a poisoning, call 1-844-POISON-X (1-800-463-5060 in Quebec), or 911 in an emergency (Health Canada).
Prefer a measured dose?
Ready-made edibles that are lab-tested and state their THC per piece let you skip the strength math. GasDank offers same-day delivery across Toronto and the GTA, usually within 1 to 2 hours, and mail order across Canada, and the menu carries lab-tested products: browse edibles or chocolates. Customers must be 19 or older (21 in Quebec), with ID checked at the door.
