A&W-Style Root Beer Float in a Frosted Mug

Why You’ll Love This Recipe

• True soda-fountain technique for that pillowy, long-lasting foam and frosted mug chill.
• Exact ratios and temperatures so every float tastes like an old-school A&W classic.
• Only a handful of ingredients, ready in minutes once everything is cold.
• Easy to scale for parties and endlessly customizable with fun add-ins.

Grocery List

• Produce: Fresh mint sprigs (optional garnish)
• Dairy: Vanilla ice cream (3 cups for 2 floats; more if scaling)
• Pantry: A&W root beer (2 x 12 fl oz), whipped cream, maraschino cherries, chocolate syrup, paper straws

Full Ingredients

For 2 Classic A&W-Style Root Beer Floats

• 3 cups vanilla ice cream (about 6 x 1/2-cup scoops; ~675 g), very cold and firm
• 24 fl oz A&W root beer (2 bottles/cans at 12 fl oz each), chilled to 34–36°F (1–2°C)
• 2 clear glass mugs, 16 fl oz each, frozen for at least 30 minutes at 0°F / −18°C

Optional Garnishes and Add-Ins

• 1/2 cup lightly sweetened whipped cream (homemade or canned)
• 2 maraschino cherries, drained
• 2 teaspoons chocolate syrup (for a Brown Cow twist)
• Fresh mint sprigs, for fragrance and color

Step-by-Step Instructions

Step 1: Frost the mugs

Place two 16 fl oz clear glass mugs into the freezer at 0°F / −18°C for at least 30 minutes (up to overnight). For a thicker frost, quickly rinse the mugs with cold water, shake off excess, and freeze. The thin film of water helps create that signature frosty exterior when the mugs hit subfreezing temps.

Step 2: Chill the root beer

Refrigerate two 12 fl oz bottles or cans of A&W root beer until they read 34–36°F (1–2°C), about 2 hours in the fridge or 20 minutes in an ice bath. Keep them unopened and upright to preserve carbonation. Do not freeze the soda; ice crystals can disrupt the bubbles and affect flavor.

Step 3: Pre-scoop the ice cream

Using a 1/2-cup scoop (about a 2.5-inch scoop), portion 3 scoops per mug (1.5 cups per serving). Set the scoops on a parchment-lined plate and return to the freezer for 10 minutes. Firm, very cold ice cream melts more slowly and supports a taller, creamier foam.

Step 4: Prime each frosted mug

Remove mugs from the freezer. Add 1–2 tablespoons of cold root beer to the bottom of each mug. This thin cushion reduces splashing and gives you a head start on that creamy foam without over-agitating the pour.

Step 5: Add the scoops

Nestle 3 frozen scoops of vanilla ice cream into each mug. Aim for a little space between scoops so the root beer can flow around them and release carbonation evenly, creating a smooth, velvety head.

Step 6: Pour for maximum foam

Hold the mug at a 45-degree angle. Slowly pour root beer down the inside wall, letting it slide under and around the ice cream. Fill about one-third of the way and pause 10–15 seconds to allow the foam to rise. Continue with one or two more short pours until the liquid line sits about 1/2 inch below the rim and a creamy dome of foam crowns the top. Each mug will use roughly 12 fl oz of root beer.

Step 7: Finish and serve

Top with whipped cream and a cherry, or drizzle with chocolate syrup if you like. Add a long-handled spoon and a straw. Serve immediately while the mug is frosty and the foam is plush—ideally within 5 minutes of pouring.

Pro Tips

• Ratio rules: For that classic balance, use about 12 fl oz root beer to 1.5 cups ice cream per 16 fl oz mug.
• Keep tools cold: Chill your scoop, spoons, and even straws for 10 minutes to slow melting.
• Do not shake the soda: Agitation knocks out carbonation and collapses the foam.
• French vanilla vs. vanilla bean: French vanilla (custard-style) yields a slightly richer, denser foam; vanilla bean offers brighter vanilla notes.
• Serve in clear glass: Seeing the layers—dark soda, creamy ice cream, and tan foam—makes the experience feel like a true soda fountain treat.

Variations

• Brown Cow: Add 1 teaspoon chocolate syrup to the bottom of the mug and 1 teaspoon on top before serving.
• Black Cow: Swap vanilla ice cream for chocolate ice cream and proceed as directed.
• Blended Root Beer Freeze: Blend 1.5 cups ice cream with 8 fl oz root beer until thick; pour into a frosty mug and top with a splash of soda for a foamy cap.
• Adults-Only: Add 1 ounce vanilla vodka or bourbon per mug. Enjoy responsibly, 21+ only.

Storage & Make-Ahead

Root beer floats are best made to order and enjoyed immediately. For easy entertaining, pre-scoop ice cream onto a parchment-lined tray and freeze solid for up to 24 hours. Keep mugs in the freezer, soda in the fridge, and assemble right before serving. Leftover floats do not store well; melt and dilution are inevitable.

Nutrition (per serving)

Approximate values for one 16 fl oz float made with 1.5 cups vanilla ice cream and 12 fl oz A&W root beer: 580 calories; 21 g fat; 90 g carbohydrates; 87 g sugars; 6 g protein; 220 mg sodium. Values vary by brand and ice cream style.